LONDON, ENGLAND, UNITED KINGDOM (SEPTEMBER 15, 2017) (REUTERS) – An improvised explosive device exploded on a packed rush-hour commuter train in London injuring 22 people on Friday (September 15) in what police said was the fifth terrorism incident in Britain this year.

A home-made bomb exploded on a packed rush-hour commuter train travelling from Wimbledon in south London towards the city centre.

Passengers on board a train fled as fire engulfed a carriage at Parsons Green underground station in West London after the explosion at 8.20 a.m. (0720 GMT). Some suffered burns while others were injured in a stampede to escape.

Metropolitan Police declined to answer whether the authorities knew who was responsible or if the suspected bomber had been on the train, saying it was a live investigation which was being assisted by the intelligence services.

Prime Minister Theresa May was due to chair a meeting of Britain’s emergency response committee later on Friday, her office said in a statement.