A New Jersey police officer is accused of firebombing a police captain's home where the captain was inside with his wife, two children and elderly mother, prosecutors said.

Officer Michael A. Dotro, 36, was arrested at his home in Manalapan Thursday. He faces charges of attempted murder and aggravated arson.

Prosecutors said Dotro, who worked with Captain Mark Anderko in the Edison Police Department, intentionally set fire to Anderko's home in Monroe Township at about 4 a.m. Monday. The blaze was extinguished within about 15 minutes but heavily damaged the two-story colonial.

Anderko was inside the house at the time with his wife, two children and 92-year-old mother, prosecutors said. The children's bedrooms were in front of the house, their windows inches away from where the aluminum siding melted from the heat of the flames.

Neighbor Haarika Reddy said the smoke detector couldn't pick up on the fire immediately, but the family dog sensed the flames and woke Anderko's wife, who in turn alerted the rest of the family.

No one was hurt.

Dotro, who has been an Edison police officer for nine years, was suspended from his job with pay. Bail has been set at $5 million.

Lawrence Bitterman, the attorney for Dotro, told NBC 4 New York it was "completely incomprehensible that Mike would be capable of something like this."

Officials did not disclose a motive.

Anderko, who has been on the Edison police force for 24 years, is one of several defendants in a lawsuit filed by another captain in the department, which has been embroiled in controversy for decades and internal lawsuits for the last several years.

The Star-Ledger reported in December that the Edison Police Department's internal affairs unit is accused of failing to pursue officers accused of brutality, and had collected information on civilians and politicians. Dotro, according to the Star-Ledger, was the subject of some brutality complaints.

Both the Middlesex County prosecutor's office and the state attorney general's office, who have been investigating the Edison Police Department, are looking into the arson.

Capt. Bruce Polkowitz, the president of the local police union, said Wednesday he was stunned by the attack on Anderko's home.

"It's unprecedented. I've never heard of anything like this, an attack on a police officer," he said. "Mark is a genuinely good person, a great family man. This whole police department, from a union point of view, we're doing whatever we can to help him out. I spoke to him yesterday, he's as good as can be expected. Our hearts go out to him."

-- Pat Battle and Andrew Siff contributed to this report.