Swedish police say they have found drugs on board a tour bus used by Canadian pop singer Justin Bieber.

Police spokesman Lars Bystrom said a small amount of drugs and a stun gun had been found when officers raided the empty bus parked under the Globen concert venue in Stockholm, where the singer was performing on Wednesday.

He declined to identify the drug, saying it had been "sent to a laboratory for an analysis".

The police went onto the bus and searched it and found a small amount of narcotics. We don't know who had the drugs or who smoked them, so it will be hard to link them with any individual Kjell Lindgren Stockholm police spokesman

No-one has been arrested.

Police acted after smelling marijuana coming from inside the bus when it was parked outside the hotel where the singer was staying.

The drug squad was alerted and searched the bus after it carried a group of people to the concert venue.

Police say there are no suspects and won't be taking the matter any further.

Police spokesman Kjell Lindgren said: "The police went onto the bus and searched it and found a small amount of narcotics.

"We don't know who had the drugs or who smoked them, so it will be hard to link them with any individual."

Justin Bieber is in Stockholm on the European leg of his Believe world tour.

When he was in London in March the Canadian singer caused controversy when he was late on stage for a concert at the 02 Arena.

A few days later he made headlines again when he confronted photographers outside his central London hotel.

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