Lubbock, TX, police officers questioned a Texas Tech University student about a stolen gun hours before he shot and killed a campus police officer , authorities said Thursday.

Hollis Daniels III was driving a car that matched the description of one driven by a person suspected of stealing a gun Sunday evening from a Lubbock home, city police Chief Greg Stevens said at a news conference. He said Daniels, 19, apparently threatened someone at the home, but he declined to say whether Daniels is suspected of stealing that gun, reports the Associated Press .

The officers who stopped Daniels' car later let him drive off because they didn't have probable cause or Daniels' permission to search his car, Stevens said.

On Monday night, campus police officer Floyd East Jr. went to check on Daniels because there had been reports of a man acting erratically who may be armed. While there, he found drugs and drug paraphernalia, and he arrested Daniels for possession and took him to the station, authorities say.

Stevens said Daniels was searched, but he declined to say whether it was before or after he and East left for the station.

"He was searched during his time in custody but unfortunately he was able to gain access to a weapon," Stevens said.

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