The brother of a Muslim terrorist who attacked two Brussels police officers with a knife has been charged with terrorism offences, the Belgian federal prosecutor said on Friday.

Aboubaker D., the brother of the terrorist Hicham Diop, was “charged with participation in the activities of a terrorist group”, the prosecutor said in a statement.

Aboubaker D., a Belgian national born in 1970, was arrested on Thursday. Police shot Hicham Diop in the leg and arrested him after he attacked two police officers, one male and one female, with a knife in the Schaerbeek area of the Belgian capital on Wednesday.

Prosecutors have charged 43-year-old Diop with “attempted murder in a terrorist context” and participating in terrorist activities.

Media reports said Diop was a kickboxing former soldier who had served until 2009 and who had ties to terrorists who had gone to fight in Syria.

Belgium remains on its second-highest level of terror alert in the wake of deadly suicide bombings targeting Brussels’ airport and metro system on March 22 in which 32 people were killed.