The suspect in an assassination attempt on Slovak Prime Minister Robert Fico may not have been just a “lone wolf” as previously believed, the interior minister said on Sunday, as security services try to shed light on an attack that sent shockwaves through Europe.

Fico is no longer in immediate danger but is still in serious condition after being hit by four bullets on Wednesday.

Interior minister Matus Sutaj Estok said an investigation team had been set up, which would also look into whether the suspect acted as part of a group of people that had been encouraging each other to carry out an assassination.

One factor suggesting the involvement of other persons was that the suspect’s internet communications were deleted two hours after the assassination attempt, but not by the suspect and most likely not by his wife, Estok said.

This indicated “the crime may have been committed by a certain group of people”, Estok told a news conference.