VERDEGRIS, Okla. -- A woman and her three children were found dead in an Oklahoma home on Thursday evening in what may be a murder-suicide following an hours-long standoff, authorities said.

The names of the victims weren't immediately released.

The standoff began in the small town of Verdigris, a suburb east of Tulsa, after a woman told a patrolling police officer at around 4 p.m. that another woman with a gun held her hostage in a garage, Police Chief Jack Shackleford said, KOKI-TV reported.

The woman also said there were children in the home and the officer called for reinforcements, Shackleford said.

Several agencies surrounded the house, including a SWAT team from the Cherokee Nation.

Authorities entered the home around 7:30 p.m. and found the bodies of the woman and three children, believed to range in age from several months to around 11 years old.

A handgun was found at the scene and the killings are being investigated as a murder-suicide, authorities said.

Shackleford said officers went to the home several times in the past on domestic and mental health calls, KOKI-TV reported.