Pittsburg police ended up shooting a 20-year-old son after his mother reported he was acting irrationally, as well as accidentally shooting the young man’s father and 17-year-old brother in the process.

Capt. Ron Raman said the Tuesday night shooting of the three family members – all nonfatal – will be investigated by Pittsburg Police Department and the Contra Costa District Attorney’s Office. The officer involved in this shooting has 20 years of experience in law enforcement, Raman said.

This was the first officer-involved shooting of 2016, Raman said, adding to NBC Bay Area that it is "unfortunate and tragic" that "the suspect's irrational actions caused two family members to get injured. He added that both were behind a dark security gate "and our officers could not see them."

The multiple shootings unfolded just after 9 p.m. when officers were called out to the1500 block of Kingsly Drive for a domestic disturbance call. The mother of 20-year-old Rigoberto Gutierrez called 911 saying her son was armed and was “acting irrational” and was most likely under the influence of drugs. She told dispatchers that he was on the porch of the home and demanding to be let inside, Raman said. Through a security screen door, the family members could see he was armed with a gun and had pointed it at his father several times, Raman said.

Officers arrived and immediately told Gutierrez drop his weapon. He was “un-cooperative refusing to comply,” Raman said.

He reached for a gun in his waistband, Raman said, and the officer fired at him.

At least two of the rounds went through the security screen where the Gutierrez's father and 17–year-old brother were standing, Raman said, and both were struck by bullets. The father was shot in the stomach and has been treated and released. The brother was shot in the leg and isin stable condition recovering from his injuries.

Raman said Gutierrez expected to survive and will be transported to Contra Costa County Jail once he is released from the hospital for assault with a deadly weapon and additional weapons related charges. His handgun was recovered at the house.

"Fortunately, everyone is expected to survive," Raman said.