BOSTON (CBS) – Massachusetts Governor Charlie Baker says his son A.J. will cooperate with the U.S. Attorney’s investigation into an allegation he sexually assaulted a woman on a flight to Boston earlier this month.

The incident was first reported Friday by WBZ-TV I-Team Chief Investigative reporter Cheryl Fiandaca. Sources told her it happened on June 20 aboard a JetBlue Flight from Washington, D.C. to Boston.

According to the sources, an adult female passenger told State Police that Andrew Baker, who is known as A.J., groped her breast on that flight. The woman allegedly told authorities that Baker refused to stop touching her and that she needed the help of flight attendants to move to another seat on the plane.

A passenger on that flight told the I-Team that they saw police board the plane and remove a man and that a woman was visibly upset. Sources say police spoke to the alleged victim and took Baker off the flight, but the Governor’s son was not arrested or summonsed to court. The State Police had no comment on the incident.

WATCH: Raw Video Of Baker News Conference

The governor addressed the issue for the first time in public Monday in a brief news conference outside his office at the State House.

“This is a personal matter for my family,” Baker said. “My family and I expect a thorough review to take place. We also expect the review will be fair and completely independent from this office. State authorities are not involved in this matter.”

Baker would not answer questions about what his son said to him about the incident.

“I love my son, but obviously these allegations are serious and they require an independent review, which is why he will cooperate with the U.S. Attorney’s Office,” the governor told reporters. “Look, I love my son, but this review needs to be done by the U.S. Attorney’s Office, A.J. needs to cooperate and we expect that that’s what’s going to happen.”

When reached for comment by WBZ-TV Monday, the U.S. Attorney would not confirm nor deny an investigation.