BRIDGEPORT, Conn. – A minivan that rolled into a park pond on the Fourth of July, killing a woman and three children inside, had no mechanical defects, authorities said Wednesday.

The deaths remain under investigation, but the finding supports the idea that a toddler inside the vehicle may have put it in gear.

The state Department of Motor Vehicles inspected the 1999 Plymouth Grand Voyager in which Michelle McIntosh, 39, died along with her son, 2-year-old David McIntosh, her nephew, Jayden Wilson, 6, and family friend Julia Boyd, 3.

They were headed to a picnic when McIntosh stepped out of the van to ask friends in a vehicle behind her where they should park. Somehow, the van began rolling away and McIntosh ran frantically after it, managing to climb inside before it sank.

The state medical examiner previously ruled the deaths accidental drownings.

A 9-year-old girl seated in the friends’ vehicle reported seeing David climb from the back seat to the front after Michelle McIntosh got out of the van, police Capt. Lynn Kerwin said. The child did not see the boy touch the gearshift, but family members have said he was fascinated with pretending to drive.

The inspection confirmed that the vehicle did not have a brake-shift interlock, which requires the driver to step on the brake to shift the vehicle out of park, Kerwin said.

“To me, that just lends more to the theory that the child could have been a factor in the whole chain of events,” Kerwin said Wednesday, while emphasizing that no conclusions have been reached.

Automakers reached a voluntary agreement last year to have brake interlock systems, already standard on many vehicles, in all new vehicles by 2010.

A service of the Associated Press(AP)