Two suicide bombers who attacked the international airport in Brussels have been named by Belgian media as the brothers Khalid and Brahim el-Bakraoui, the BBC reports.

The RTBF broadcaster said the pair were known to police. A third man pictured with them at the airport is still being sought.

Twin explosions at the airport and another at a metro station on Tuesday left about 34 dead and 250 wounded.

Belgium is observing three days of national mourning.

So-called Islamic State (IS) has said it was behind the attacks and warned that more would follow.

A minute’s silence for the victims will be held at midday (11:00 GMT).