The man who narrowly missed wreaking carnage in Stockholm with Sweden's first suicide bombing may have had links to radical Muslim preacher Abu Hamza, media reported Thursday.

They also said that other voices could be heard on an audio message the suicide bomber sent out before Saturday's attack near a busy pedestrian shopping street in the Swedish capital.

The Svenska Dagbladet daily reported, quoting sources with insight into the case, that British police were looking into a possible connection between Taimour Abdulwahab, who is strongly believed to have been the Stockholm bomber and Egyptian-born Hamza.

Hamza, the former imam of the once-notorious Finsbury Park mosque in north London, was jailed in Britain for seven years in 2007 for inciting followers to murder non-believers.

TV4 meanwhile reported that it had hired a sound technician to analyse the audio message the Stockholm bomber sent to police and media shortly before he first blew up his car and minutes later himself.

"There are at least two people" heard on the message, sound technician Johan Oehgren told the commercial broadcaster.

"It is not possible to speak while breathing in. You can clearly hear there is someone else in the room," he added.

Police have yet to confirm that Saturday's bomber, who was the only person to die, had helpers.

The bomber was carrying a cocktail of explosives and is believed to have detonated a small charge prematurely, prosecutor Tomas Lindstrand said Monday.

Two other people were injured when his car exploded nearby minutes earlier.