Flames seen on London Tube train after explosion reported Reuters

Celebrities from across the showbiz sphere have taken to social media to express their anger and shock as new details of the Parsons Green tube explosion continue to emerge.

More than a dozen commuters were left injured when a device on the southbound District line exploded during morning rush hour on Friday (15 September). Passengers described a "fireball" in the carriage, which caused burns, and British police said that they were treating it as a "terrorist incident".

Before the authorities released a statement, Good Morning Britain host Pier Morgan already had a few theories of his own. He tweeted: "Hmmm. Who takes a big bucket with wires like that onto the tube? This Parsons Green incident was not an 'accident'"

Former Eastenders actor Leslie Grantham said he was grateful that there hadn't been multiple tragedies, writing: "Thank their lucky stars that Parsons Green Tube is not underground. Probably saved a hell of a lot of lives. Stay strong."

Keavy Lynch of Irish girl group B*Witched: "I hope all London folk are safe!! #ParsonsGreenExplosion #KeepSafeLondon"

X Factor stars Reggie 'n' Bollie said: " Just heard of the London tube explosion. Our thoughts to all affected in #ParsonsGreen Praying for the day all this #terror will stop."

Controversial columnist Katie Hopkins was slammed as "insensitive" after making jokes about the incident on Twitter just moments after it occurred. Sharing a widely-circulated image of a white bucket in a Lidl back with wires sticking out of it she told her her 813K followers: "It's going to be a busy day @LidlUK."

Following a barrage of condemnation, she added: "My angrier self would joke and try to capitalise on #ParsonsGreen, I just hope everyone is ok. Thoughts and prayers."

London Mayor Sadiq Khan has condemned the "hideous individuals" behind the attack in a statement posted on Facebook, adding defiantly that: "We will never be defeated."

"As London has proven again and again, we will never be intimidated or defeated by terrorism," he wrote. "My sincere gratitude goes to all our courageous emergency responders and the TfL staff who were first on the scene. I urge all Londoners to remain calm and vigilant".

Piers Morgan
Piers Morgan attends the Vanity Fair, Barneys New York and The Weinstein Company celebration of 'Silver Linings Playbook' in support of The Glenholme School on February 20, 2013Getty