Boston Mayor Michelle Wu was inside a police car that collided with another vehicle on Tuesday in what she said today left her a little sore, but she did not address fully why the blue lights were on as the vehicle crossed on a red light.

“There’s a review that happens,” she said when peppered on why the car’s lights were on crossing the intersection against a red light. She did say they were heading to “an engagement at the Copley Library. I didn’t end up making it there.

“It happened pretty fast,” she added. “I was on my phone and not really seeing what was happening as the blue lights were on at that intersection.”

Wu said she was unfamiliar with what the policy was regarding when police lights and sirens should be deployed, and did not answer questions, when asked directly if their use in this particular situation was appropriate.

The mayor did say, however, that the situation wasn’t an emergency.

The two-car crash occurred on Hyde Park Avenue, a spokesperson for the Boston Police Department said.

Wu praised police, including one working a detail nearby, and EMTs who rushed to help all involved — including passengers in the other vehicle in the crash.

A city spokesperson had confirmed the “mayor was a passenger in a vehicular crash” in a Tuesday night statement.

“Thankfully no one sustained any major injuries,” the Wu spokesperson said. “The Boston Police Department will conduct an investigation of the incident as they do with all crashes involving departmental motor vehicles.”

An incident report released on Wednesday morning didn’t identify the mayor by name, listing her only as a “passenger who is known to the Commonwealth.”

In the police report, the officer driving the mayor, Keyanna Smith, wrote that their unmarked cruiser was heading down Blakemore Street, and approaching Hyde Park Avenue, with its “lights and sirens activated.”

The officer stopped their car at a red light, and then “slowly approached the intersection to ensure that the oncoming traffic traveling outbound on Hyde Park Avenue” was able to “see and hear” the cruiser entering the intersection, the report stated.

The first lane of traffic “observed the cruiser’s lights and sirens and came to a complete stop,” but a car traveling down the second lane did not as the officer’s car was crossing through the intersection,” the report stated.

The black SUV, driven by a woman with her young son in the backseat, “collided into the driver’s side of the cruiser,” according to the report.

The report further states that the officer could not avoid the crash due to the “fast approach of the other vehicle,” which “did not stop or slow down for the cruiser’s lights and sirens.”

Wu stated that she felt a “minor pain to the right side of her body,” but declined medical attention at the scene. She was planning to potentially seek treatment at a later time, the report stated.

The woman driving the other car and her young son were taken by ambulance to a hospital. The woman had initially declined treatment, stating that they were both “alright,” the report stated.

The officer driving the mayor “felt pains to the left side of the body,” and was also taken to the hospital for treatment, according to the report.

The cause of the crash is under investigation, a BPD spokesperson said.