State and local law enforcement officers knew a Casper couple was allegedly bringing a large amount of heroin and methamphetamine into the Casper area on Saturday and planned to stop them before the couple took off, firing two guns at officers and assaulting an elderly woman as they fled.

Christopher Eads, 34, faces a total of 11 charges: one count each of conspiracy to distribute meth and heroin, one count of delivering meth, six counts of aggravated assault, one charge of felony property destruction and one count of possession of a deadly weapon with unlawful intent.

He could face up to 135 years in prison if convicted on all counts.

His girlfriend, Santana G. Keener, was charged Tuesday in Converse County Circuit Court with burglary, felony possession of heroin and possession of heroin with intent to deliver. She could face up to 37 years in prison if convicted.

Charging papers say agents of the Wyoming Division of Criminal Investigation knew Eads and Keener allegedly drove to Colorado on Saturday to obtain a large amount of meth and heroin, because agents had been tracking Eads since late April.

Several confidential sources and informants told agents that Eads was working with another man to bring large quantities of heroin from Denver, Colo. to sell in the Casper area. Eads allegedly made trips to buy more drugs several times each week.

Agents learned that Eads mainly sold heroin, but also obtained small quantities of meth to sell in order to support his heroin habit. He reportedly was a heavy heroin user.

Eads drove a dark-colored Toyota Sequoia and often traveled with Kenner, buying half a pound of black tar heroin and up to two pounds of meth at a time in Denver, multiple times each week.

Sources also said Eads made frequent trips to Douglas.

In May, agents conducted a controlled buy from Eads, in which a confidential source bought one-eighth of an ounce of meth at Eads' Casper home in the 900 block of South Melrose Street.

On Saturday, agents were waiting for Eads and Kenner to return from Colorado, having learned Friday that the pair was allegedly making a drug run. The plan, in coordination with Wyoming Highway Patrol troopers, was to stop the pair on I-25 as they approached Casper.

At about 9:30 p.m., Kenner was driving the Sequoia with Eads in the passenger seat, when she passed a highway patrol car parked in the median. As she later told investigators, she watched in her rearview mirror as the trooper turned around and began following them.

She kept driving northbound, but soon saw a second trooper parked in the median turn and follow as well. At that point, Keener said, she knew what was going on.

As troopers activated their emergency lights and tried to stop the Sequoia at about 9:30 p.m., Keener pushed the gas pedal down and took off.

Eads reportedly said he was not going back to prison, adding, "this [is] the end," according to an affidavit.

Kenner fled northbound, but said she was "sonic[ed]," claiming officers had used a sonic device to deactivate the electronics in the SUV. As she tried to get the Sequoia started again, Eads allegedly tried to reach across her for a Kel-Tec 9mm pistol that was in the driver's side door.

He couldn't reach it, Kenner said, so she handed him the gun and Eads started shooting at officers out the passenger window.

Just before the Sequoia rolled to a stop, Kenner was able to get it running again. She continued northbound on I-25.

A moment later, Eads switched seats with Kenner and continued driving until he hit spike strips near mile marker 180. Both front tires were punctured.

Even so, Eads kept going. He turned off the lights, drove into the median, stopped for a moment, then turned and went southbound -- directly toward pursuing officers.

While the Toyota was stopped in the median, troopers and agents had exited their vehicles and taken cover behind them. When Eads began driving toward them, the officers opened fire, but didn't hit either of the suspects.

Eads drove on at speeds of roughly 90-100 mph, with two flat tires and no lights.

As Eads fled, court documents say, Kenner searched the floorboard for the keys to a safe containing a large amount of meth and heroin. Before she found the keys, she tossed the 9mm pistol out the window.

Keener then got into the safe, grabbed a plastic bag full of meth and threw it out the window as well. Agents searching for evidence on Saturday found the evidently destroyed bag and collected as much of the meth as they could.

The pair kept heading south, with Eads trying to stop the Sequoia so he could steal another vehicle. However, because the SUV had already hit spikes, Eads couldn't bring the Toyota to a halt.

Kenner said at that point, Eads was "freaking out" because he couldn't stop. He took a .22-caliber pistol from the center console and fired five rounds -- the only ammunition in the magazine -- at pursuing officers.

Keener claimed Eads was trying to shoot out their tires.

Eads eventually left the interstate at exit 165 -- the Rolling Hills exit -- and headed north into Glenrock. Kenner threw the second pistol out the window as well.

Troopers had backed off after the shooting, trying to follow at a safer distance but having difficulty seeing the darkened SUV. Agents, state troopers, Converse County Sheriff's deputies and Glenrock police officers tried to find and stop the Toyota.

Officers eventually found the Toyota unoccupied at the intersection of Fourth and Fir Streets. As they started to look for Eads and Keener, an EMS call came over the radio for an elderly woman bleeding from her head in the 600 block of South Fifth Street.

A lieutenant with the Wyoming Highway Patrol was nearby blocking traffic in order to form a perimeter, and responded to the EMS call. He searched the home, but didn't find any sign of Eads or Keener.

The elderly woman would later tell officers she was watching television at about 10 p.m. when she heard a loud "bang" at the back door.

It was probably the sound of Eads kicking in the side door of the woman's detached garage. Court documents say Keener and Eads found a small SUV inside, but no keys.

The elderly woman, after hearing the noise, first thought a tree limb may have fallen on her roof. But when she opened the back door to check things out, Eads -- who had approached the house in an attempt to go in through a window -- appeared out of "nowhere."

He allegedly grabbed the woman's wrist, shouting, "Give me your keys" several times as the victim tried to pull away from him.

The woman stepped back into her house, but Eads held on, following her inside. He pushed the woman backward, and she fell, hitting her head. The blow dazed her, leaving her scared and afraid for her life.

Eads took the woman's keys and headed back to the garage. He didn't bother opening the main garage door, backing right through it as he and Keener took off in the woman's silver Chevrolet Equinox.

The victim ended up getting 18 staples in her scalp to close the cut. She also suffered a broken rib and broken toe, along with severe bruising on her wrists and left shoulder.

Officers continued searching the area for Eads and Keener, looking for the Equinox. That vehicle was later found in a drainage ditch near Fort Laramie Street in northeast Glenrock.

Court documents say Eads then assaulted a Glenrock police officer and stole his patrol car. Keener later told investigators she heard someone, evidently the officer, shouting, "Let go of my gun!"

Keener was in the ditch when Eads got into the police car. He pulled up to her and told her to get in, but Keener had trouble getting out of the ditch. So, Eads took off.

Officers later found Keener hiding in a field next to the ditch about 400 yards from where the Equinox was discovered.

Kenner was arrested and taken to the Converse County Detention Center, where a search allegedly revealed some 18 grams of heroin. Police later found heroin in Kenner's purse inside the Sequoia.

After ditching Kenner, Eads continued running from officers. He didn't get far before crashing the stolen police vehicle near Deer Creek Bridge at milepost 163.

But that didn't stop Eads, who allegedly stole yet another vehicle and took off toward Casper.

Officers from numerous law enforcement agencies chased Eads into Casper, where Eads again hit spike strips, ultimately coming to a stop in the parking lot of Dayton Transmission at 1610 East F Street.

After a three-hour standoff and negotiation in which officers were heard telling Eads, "We don't want to have to kill you," Eads was arrested and taken to a hospital. The Natrona County Sheriff’s Office Special Response Team had to be activated during the standoff.

Assistant District Attorney Trevor Schenk said Eads remained hospitalized early Wednesday. He has yet to make his initial appearance in Natrona County Circuit Court.