NEW YORK — The news wires are abuzz with several violent incidents that happened over the weekend in the U.S., continuing to tarnish the country’s reputation as a safe destination for international travellers.

Authorities questioned several people early Monday after a car stop in New York City as they worked to determine whether there was a connection between several explosive devices found in two states in two days. An explosion rocked a bustling Manhattan neighbourhood Saturday night, and an unexploded pressure cooker device was found blocks away. There was also a pipe bomb blast earlier Saturday in a New Jersey shore town, and five explosive devices were found near a New Jersey train station late Sunday.

Furthermore, authorities are investigating the stabbings of nine people at a Minnesota mall as a potential act of terrorism, a finding that would realize long-held fears of an attack in the immigrant-rich state that has struggled to stop the recruiting of its young men by groups including the Islamic State.

Democratic Gov. Andrew Cuomo, touring the site of Saturday’s blast that injured 29 people in Manhattan’s Chelsea neighbourhood, said there didn’t appear to be any link to international terrorism.

Authorities said the Manhattan bombing and New Jersey pipe bomb didn’t appear to be connected, though they weren’t ruling anything out. The pipe bomb exploded in Seaside Park, New Jersey, before a charity 5K race to benefit Marines and sailors. The race was cancelled and no one was injured.

Late Sunday, five suspicious devices were found near a train station in Elizabeth, New Jersey. Elizabeth Mayor Christian Bollwage said the devices were found in a bag in a trash can by two men who reported seeing wires and a pipe coming out of the package. One of the devices exploded as a bomb squad used a robot to try to disarm it. No injuries were reported.

The Chelsea explosion left many rattled in a city that had marked the 15th anniversary of the 9-11 attacks only a week earlier and that is scheduled to hold a United Nations meeting today to address the refugee crisis in Syria.

Witnesses described a deafening blast that shattered storefront windows and injured bystanders with shrapnel in the mostly residential neighbourhood on the city’s west side.

One New Yorker, Anthony Stanhope, was in his apartment when the blast went off nearby. He said at first he thought it was thunder and lightning.

“Then all of a sudden, car horns went off, and I thought, ‘Oh, my God, this isn’t lightning. This is too loud,” Stanhope said. “This is a bomb.”