Oct 11, 2021; Boston, MA, USA; General view of the elite runners at the start of the 2021 Boston Marathon. Mandatory Credit: Brian Fluharty-USA TODAY Sports/
Oct 11, 2021; Boston, MA, USA; General view of the elite runners at the start of the 2021 Boston Marathon. Mandatory Credit: Brian Fluharty-USA TODAY Sports/ Reuters / Brian Fluharty

Boston officials will increase the number of police around subway stations ahead of Monday's Boston Marathon after a mass shooting in a New York subway but stressed there was no known threat to the race and voiced confidence in it going ahead.

A gunman wearing a gas mask set off a smoke bomb and shot 10 people in a New York City subway car during Tuesday's morning commute, authorities said. None of the wounded had life-threatening injuries, they added, and a manhunt for the perpetrator was underway.

"There is no known credible threat to the marathon. Like everybody else, we're monitoring the situation in New York," Boston Police Superintendent-In-Chief Gregory Long told a news conference on Tuesday, adding that his department had been in touch with their New York counterparts and the FBI.

"In the short term you can expect to see an increased police presence around MBTA stations the next couple of days through the weekend. In terms of Monday, depending on what kind of information we have and intelligence, we'll adjust our assets accordingly around the marathon," he said.

Security is of top concern for local authorities with heightened measures put in place after the Boston Marathon bombing attacks of 2013.

The Boston Police Department will have uniformed and undercover officers along the marathon route on Monday, and set up cameras and checkpoints along the Boston part of the race to monitor the crowd.

The city is expecting especially large crowds on Monday because the marathon is returning to its traditional April race date for the first time in three years following pandemic-related disruptions, while baseball's Boston Red Sox will also be playing at home that day.

Boston Athletic Association (BAA) President Tom Grilk expressed his confidence in the ability of the city authorities to safeguard the event.

"We are the grateful beneficiaries, we at the BAA and all involved in the marathon, of the work of all the agencies you see represented here and many others. So concerned? Not concerned in any unusual way," he told the same news conference.

"Alert, vigilant in every possible way. But knowing that that vigilance is in the hands of all the right people we're very comfortable to proceed."