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SYDNEY - A childish prank -- detonating a stink bomb on a commuter train -- sparked a counter-terrorism investigation in Sydney today.
Two teenage boys are accused of detonating the prank devices -- which have a strong odour but are harmless -- on a commuter train on the northern line at about 10.30am (AEST) today.
The boys, who have been captured on security camera footage but have not been arrested, then let one off at St Leonards railway station in Sydney's north.
Assistant Police Commissioner Dave Owens said passengers began to panic after hearing an explosion on the train between St Leonards and Wollstonecraft stations.
The boys had got off the train minutes earlier at St Leonards station -- where a second device was let off at an unattended ticket booth.
Police, including the elite counter-terrorism command, launched into action after numerous triple-0 callers reported an explosion on a train.
Passengers were evacuated at Wollstonecraft while the train was taken to North Sydney railway station, where police established a crime scene.
Mr Owens said police had thrown lots of resources into the response and didn't find the prank funny.
"It would have been terrifying. You're on a train, you hear a loud bang, the logical conclusion that people drew was (that it was) probably a terrorist attack," Mr Owens told reporters.
"It wasn't, we don't treat it as a joke, we don't see it as funny at all.
"We had to throw a number of resources, from local area commands, regional police, and from the counter-terrorist community into this incident."
- AAP
