(CNN) -- The Texas prosecutor shot to death in broad daylight outside a courthouse had feared for his life and carried a gun to work, according to a Dallas attorney describing herself as his friend.
Colleen A. Dunbar told CNN that she spoke with Kaufman County Assistant District Attorney Mark Hasse on January 24, and he told her he began carrying a gun in and out of the county courthouse on a daily basis.
Hasse was gunned down in the parking lot while going to work Thursday. Investigators on Friday were reviewing his caseload for possible clues about what led to his killing.
Dunbar described Hasse, whom she had known for 31 years, as a lifelong gun owner and firearms lover.
"He told me he would use a different exit every day because he was fearful for his life," she told CNN.
She said that Hasse offered no specifics on why he felt threatened, but only that he did. Dunbar said she had shared her conversation with Hasse with law enforcement, and that she was "shocked" by the killing.
When told of Dunbar's statements, Chief Deputy Rodney Evans of the Kaufman County Sheriff's Department was unaware of the information.
"But," Evans told CNN, "we've got 50 people here taking phone calls so somebody may know something I don't."
There were no significant advances in the case, Kaufman Police Chief Chris Aulbaugh said Friday, but that doesn't mean investigators weren't busy.
"We've fielded numerous tips coming in from the public. We are following up on every one of them," he said.
Police say they believe one or two people committed the crime, but there are few descriptive details because they hid their faces. Police are looking for a gray or silver older model sedan in relation to the case, Aulbaugh said.
Hasse was shot several times after "a very small, very short confrontation," police said.
Investigators are looking into whether Hasse's killing was retribution for any of the prosecutions he led. Hasse was one of 13 prosecuting attorneys in Kaufman County, each of whom handled between 380 and 390 cases.
Authorities hope that an ever-growing reward for information will reveal more leads.
Donors in the area have raised $64,500 to be used as reward money, and the police chief has asked for more donations.
The Texas Rangers, the FBI and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives have joined the manhunt.
CNN's David Fitzpatrick contributed to this report.