The widow of a man fatally shot at a Planned Parenthood abortion clinic in Colorado and a woman wounded in the same 2015 attack are suing the facility over lax security, court records showed on Monday.

The suit claims that given the "long history of violence" at U.S. abortion clinics, Planned Parenthood in Colorado Springs should have implemented safeguards that would have prevented a gunman from going on a shooting rampage that left three people dead and nine wounded on Nov. 27 last year.

The wife of Ke' Arere Stewart, who was killed, and Samantha Wagner, who suffered a gunshot wound to her arm, accuse the clinic of being liable, negligent and of outrageous conduct in the suit filed on Friday in Denver District Court.

Stewart is suing for the wrongful death of her husband, and Wagner, who sustained a shattered and severed humerus bone, is asking for monetary damages to cover her medical bills and "permanent physical impairment."

Planned Parenthood "provided little or no security at (the clinic) such as an armed guard and perimeter fencing, as they do in other clinics," the lawsuit said. 

"It provided no signs, posters, verbal or any other type of warning describing the risk of physical harm, injury or death associated with entering (Planned Parenthood) properties."

The gunman accused of the rampage, Robert Dear, 58, surrendered after a standoff with police. He has been charged with multiple counts of first-degree murder, attempted murder and assault.

A spokeswoman for Planned Parenthood of the Rocky Mountains said the organization could not comment on the ongoing litigation.

"We believe that our health centers throughout the region are both safe and inviting for our patients and our staff who care for them," said Whitney Phillips, a spokeswoman for the organization.   

At least eight abortion clinic workers have been killed since 1977 and clinics have reported nearly 7,000 incidents of trespassing, vandalism, arson, death threats, and other forms of violence since then, according to the National Abortion Federation.

The judge in Dear's criminal case ruled last week that he is mentally unfit to stand trial after two state psychologists diagnosed him with a psychotic delusional disorder.

Dear proclaimed himself guilty and that he was "a warrior for the babies" in several outbursts at earlier court hearings.

Dear has been sent to a state mental hospital to undergo treatment in an attempt to restore him to competency.