A 28-year-old German-Russian citizen has been arrested in Germany on suspicion of bombing the bus carrying the Borussia Dortmund soccer team in an attack last week that officials alleged was motivated by financial greed.

A Dortmund player and a policeman were injured in the triple blasts last week as the bus was heading to the team's stadium for a Champions League game.

Investigators found notes at the scene claiming responsibility on behalf of Islamic extremists, but quickly doubted their authenticity.

Federal prosecutors said the suspect, identified only as Sergej W. in keeping with German privacy law, was arrested by a police tactical response team early on Friday in or near the southwestern city of Tuebingen.

He faces charges of attempted murder, causing an explosion and serious bodily harm.

Prosecutors said they planned to make a statement later on Friday, but revealed that the suspect had taken out a loan and bought a large number of so-called put options for shares of Borussia Dortmund, betting on a drop in the share price.

"A significant share price drop could have been expected if a player had been seriously injured or even killed as a result of the attack," they said.

Ralf Jaeger, the top security official in North Rhine-Westphalia state, said the suspect had hoped to earn millions.

"The man appears to have wanted to commit murder out of greed," said Jaeger.

Prosecutors said they traced the computer used to purchase the put options to the luxury hotel in Dortmund where the team had been staying.

They said W. had also booked a room there and placed three explosives, packed with shrapnel, along the route the bus would take to reach the stadium for their first-leg match April 11 against Monaco.

"The explosive devices were detonated at the optimum time," prosecutors said, noting that the team bus was equipped only with security glass and not reinforced glass. Several windows on the bus were shattered, injuring defender Marc Bartra. A police officer accompanying the bus also suffered trauma.

AAP

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