A 22-year-old Wichita man, who was convicted in connection with a 2010 Lawrence armed robbery, has pleaded guilty to a federal gun charge, according to U.S. Attorney Barry Grissom’s office.

D’Andre Tomlin in federal court in Wichita Monday pleaded guilty to one count of unlawful possession of a firearm after having a felony conviction. As part of his plea, Tomlin admitted that in September he possessed a Heckler and Koch 9-mm pistol. A special agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives alleged Tomlin sold the pistol to an undercover officer. U.S. District Judge Eric Melgren is scheduled to sentence him April 25, and he faces a maximum 10-year prison sentence.

Tomlin last September also had pleaded guilty to three counts of attempted aggravated robbery for his involvement in a Dec. 2, 2010, robbery of three female Kansas University students at an apartment in the 1100 block of Louisiana Street. Prosecutors accused Tomlin and his co-defendants — who were each sentenced to 11 years in prison — of entering the wrong apartment they initially planned to rob and holding the three women at gunpoint. Tomlin has not yet been sentenced in the Douglas County case.

Grissom in a statement Monday said Tomlin was the 20th defendant so far to plead guilty to a federal gun charge as a result of the 11-month ATF sting operation in Wichita targeting convicted felons who possess guns. Grissom said 67 people have been arrested on state or federal charges as part of the operation.