Earlier on Tuesday a separate Reuters witness reported scores of people running from the Arndale shopping centre, with some saying they had heard a big bang.
Manchester's Arndale Centre has been evacuated and one man has been arrested.
Conflicting reports suggested the incident might have been a false alarm amid high tensions following Monday's attack, the local media reported. The explosion occurred at around 10:30 pm on Monday night when Grande was concluding her concert with the last song.
McIlroy pulls out of BMW PGA Championship with rib injury
It's a work in progress, but overall I don't think we're in a bad spot and it will be nice to pick up some form this week. Scottish Open (July 13-16): The Ireland-Scotland double open to lead into The Open Championship is a delight to me.
Many were confused with some visibly shaken and tearful.
Police in the northern English city of Manchester are investigating an incident at the Arndale shopping centre, an officer at the scene said on Tuesday. The shopping centre was evacuated by armed police but later reopened.
Unconfirmed reports say that a suspicious package was found in the food court.
Pakistan asks ICJ for early hearing in Kulbhushan Jadhav case
Pakistan cannot execute Indian national Jadhav until it makes a final decision in the proceedings of the case, the ICJ said. The federal government, however, has not taken any decision about replacing Pakistan's attorney Khawar Quraishi.
The evacuation is now ongoing.
Police gave the news moments after confirming another man had been arrested in connection to the concert attack.
Spurs beats Man United in stadium finale to secure 2nd spot
Tottenham hope to occupy their new stadium in 2018-19 - which means home games next season will take place at Wembley. Ginola tweeted: "Farewell, goodbye White Hart Lane ".