‘We will step up patrols, but there is no threat to the city of Boston,’ Evans says

Boston Police Commissioner William B. Evans. John Tlumacki/Globe staff/File

MANSFIELD — A new concert season opened at the Xfinity Center in Mansfield with heightened security Tuesday night, just one day after a terror attack at an Ariana Grande concert in England.

Mansfield police said they would strictly enforce bag checks and arrest underage drinkers and urged concertgoers attending the Future: Nobody Safe Tour to be vigilant about their safety.

“The world we live in. If you see something, say something,” police wrote on Facebook, just hours before various hip-hop artists were to perform. “We’ve got a whole bunch of people very well trained, many of whom are wearing brightly-colored shirts and would happily speak to you about something or someone you find suspicious.”

A spokeswoman for the Xfinity Center did not immediately respond to a request for comment.

It is one of several Boston-area venues on heightened alert after a bomb detonated just outside of a Manchester arena at the conclusion of a pop concert Monday, killing 22 and injuring dozens more.

Governor Charlie Baker and Boston Police Commissioner William B. Evans said there is no immediate threat to Boston, but police will increase their patrols around concert venues and at the Boston Calling Music Festival, set for Memorial Day weekend at Harvard Stadium.

“Obviously we’re going to be taking additional precautions with respect to concerts generally,” Baker said. “I know the folks in the city around the Boston Calling concerts have already talked about that and I’m sure this will just encourage them to up their game with respect to that as well.”

After learning about the bombing, which British authorities have said was a terror attack, Evans said his department contacted other law enforcement agencies to see if there was an active threat for Boston.

“There is no threat in the city,’’ Evans said. “I just want people, as we approach Memorial Day, to feel secure. We will step up our patrols, but there is no threat to the city of Boston.’’

At the Xfinity Center, about 50 police officers were on duty, a State trooper on the scene said. Private security guards checked large bags.

Lily McGrath of Rockland said the terror attack did not make her afraid to attend the show. “We’re from Boston, where the marathon bombings happened,” said McGrath, 18, accompanied by Rico Lynch, 22, of Boston. “I’m not going to stop doing things I like because then (terrorists) win.”

But as she waited with other parents to pick up her son, Sarah Casey of Worcester said, “We’re all very concerned parents.”

Evans said people attending concerts or shows should help law enforcement and security officials by not wearing bulky clothing or bringing backpacks. “The less bulky stuff they bring, the quicker they get into the venue and the safer everyone will be,’’ Evans said.

Evans called the Manchester bombing “a tragedy. That someone would go after young people [is] a real cowardly act.’’

Evans said his department has been working with owners of nightclubs, the TD Garden, and the Boston Red Sox for years on improving security.

The Red Sox played the Texas Rangers at Fenway Park on Tuesday night. Zineb Curran, a Red Sox spokeswoman, said in an e-mail that security procedures are frequently updated “to ensure the safety of our fans . . . (and) to make sure we have all the necessary resources to keep the ballpark secure.”

Evans noted that Lansdowne Street near Fenway Park is closed as part of a perimeter security plan to stop a terrorist with a vehicle from attacking patrons. He said the city will “work with the venues to make sure they have secure perimeters, whatever they need.’’