Update [4:10 AM PST]: Almost 50 ambulances are currently present at the site.

Update [4:02 AM PST]: Greater Manchester Police says "there are a number of confirmed fatalities".

Update [3:35 AM PST]: Ariana Grande is safe, reports say.

Update [3:32 AM PST]: The area around Manchester Arena has been cordoned off, with security authorities asking people to "stay away" from the area. Ambulances and emergency teams rushing to the site.

Update [3:31 AM PST]: Some people on social media say the blast may be a balloon at the venue.

Update [3:30 AM PST]: Unconfirmed reports indicate a man has been apprehended while trying to escape during the stampede, Geo News reported.

Update [3:25 AM PST]: Services at the Victoria Park Railway Station have been suspended following the incident.

Initial report [3:20 AM PST]: Reports of a blast at Manchester Arena, UK, surfaced late Monday night, with Greater Manchester Police confirming "an incident".

American singer Ariana Grande was performing at Manchester Arena, a venue in the northern English city.

Police have issued a warning to "stay away from the area", following two blasts that led to a stampede, with almost 15,000-20,000 attendees trying to escape.

An unconfirmed number of people have been injured, sources revealed. Most of the locality has residential apartments and student hostels.

People present at the event included those who had come in from other parts of Europe.

?Additional reporting by Tanveer Khatana; editing by Haseem uz Zaman