Law enforcement officers are ratcheting up their pursuit of felons who attempt to obtain guns and ammunition.

It was an expensive trip to Walmart for 29-year-old Reuben James Zeller of Lawrence.

And not because of the bullets he had someone purchase for him.

That purchase a law enforcement informant made for Zeller on Oct. 6, 2010, in Topeka will cost him 15 years in federal prison because he was barred from possessing a gun or weapons because of his past convictions. Zeller is also accused of committing a drive-by shooting at a Topeka residence in October 2010.

U.S. Attorney Barry Grissom, the top federal prosecutor in the state, is highlighting Zeller’s recent plea agreement with prosecutors as an example of cracking down on repeat violent offenders who don’t change their ways after they get out of prison.

“They are back and hanging out with the same buddies,” Grissom told the Lawrence Central Rotary Club last month.

He and other Department of Justice officials nationally are worried the violent behavior could continue to escalate, and U.S. Attorney General Eric Holder has stressed that federal prosecutors should work with local law enforcement to get guns out of the hands of felons. Holder’s order came after 162 law enforcement officers nationally were killed in 2010. Grissom, whom President Barack Obama nominated to the Kansas post in 2010, said that was the deadliest year for law enforcement in more than two decades and that the country was on track to beat that number this year.

Grissom also highlighted a recent 11-month undercover investigation in Wichita conducted by the Bureau of Alcohol, Tobacco, Firearms and Explosives in which 67 people were charged, and authorities, with the help of local law enforcement, recovered 200 guns — including ones reported stolen and sawed-off shotguns — and illegal drugs.

Under federal law, it’s illegal for anyone convicted of a felony and drug traffickers to possess guns or ammunition.

Grissom said federal agents and prosecutors have been working with local officers to target convicted felons who might still be possessing guns. He also has said they were looking to do similar operations in the Kansas City, Kan., and Topeka areas.

“If you know who those folks are and you can find them with weapons or ammunition, we can take that person out of the community and make the community safer,” Grissom said. “We’re taking a very active stance on doing those kinds of things.”

One Topeka man, Steven Allen Contee, 33, was sentenced last week to serve seven years in federal prison for selling three shotguns with co-defendant Patrick M. Tracy Jr. to ATF agents working under cover at a hotel parking lot in Topeka on Feb. 5. Both Contee and Tracy had prior felony convictions.

Reuben Zeller, the Lawrence man who is expected to serve 15 years in federal prison, seems to fit the profile for the type of criminal federal authorities are most concerned about. According to the Kansas Department of Corrections, Zeller in 2003 received a prison sentence for a 2002 burglary in Jackson County north of Topeka. He also has a Shawnee County burglary conviction and an aggravated assault conviction from 2005 in Osage County, all of which barred him from possessing a firearm.

But during his most recent crime spree in 2010 after he was paroled in 2009, federal authorities allege through a witness that Zeller was distributing firearms and prescription drugs to people in Lawrence and Topeka.

According to the proffer for Zeller’s guilty plea in the federal case, Zeller told an informant on Sept. 27 he fired 18 rounds from a Remington 9 mm handgun into the residence of a man he had argued with earlier. He later pleaded no contest in an October Douglas County case in which he is accused of threatening someone, and as part of his federal plea agreement, Zeller will enter a plea in the Shawnee County shooting case.

About two weeks after the drive-by shooting, officers used reviewed surveillance video from a Topeka Walmart store and obtained video of Zeller giving money to a confidential informant to buy him ammunition, which he was barred from possessing as a felon.

“The things that people don’t go hunting with,” Grissom said. “They only use them in commission of crimes. We took those off the streets.”