A gunman opened fire at a prominent family planning center in Colorado, killing three people and wounding several in a standoff that dragged on for five hours before he surrendered Friday.

A gunman opened fire at a prominent family planning center in Colorado, killing three people and wounding several in a standoff that dragged on for five hours before he surrendered Friday.

A usually busy area of snow-covered Colorado Springs was placed on lockdown into the early evening, just a day after millions of Americans celebrated the Thanksgiving holiday.

Mayor John Suthers paid tribute to police for hauling the gunman into custody without further bloodshed at the Planned Parenthood building, where people scrambled into a safe room in a desperate bid to save themselves.

A police officer was among the dead, he said, while nine others -- among them five police -- were wounded. None of the injured was in a serious condition.

"I want to convey to the loved ones of the victims: this is a terrible, terrible tragedy that occurred here in Colorado Springs today," Suthers told reporters.

"Obviously, we lost two civilian victims, we mourn the loss of a very brave police officer."

Earlier, there had been fears that the unidentified gunman might have explosives with him, and police were carefully combing the scene after the siege, which came to an end when he surrendered.