VERDIGRIS, Okla. — A woman and her three children were found dead in an Oklahoma home Thursday night in what may be a murder-suicide after an hour-long standoff, authorities said.

The names of the victims were not immediately released.

The standoff began in the small town of Verdigris, an eastern suburb of Tulsa, when a police officer driving down the street saw fireworks coming from inside a home garage, according to Oklahoma State Bureau of Investigation spokesman Hunter McKee.

«It was at that point that the officer knew something was wrong and went to investigate and called for backup,» McKee said.

The officer saw what Police Chief Jack Shackleford described as Roman candle fireworks and found a woman and two children locked in a garage.

The woman said she had brought another child into the home for a supervised visitation and was met by an armed woman who took the child and locked the woman and two other children with her in the garage, Shackleford said.

Multiple agencies surrounded the home, including a SWAT team from the Cherokee Nation.

Following a three-hour standoff with no response from inside the home, McKee said officers entered the home and found the adult woman and three children dead with gunshot wounds.

The three children are 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 multiple times in the past for domestic and mental health calls, KOKI-TV reported. It was not immediately known how the two women knew each other.