Brussels schools and metro to return to normal on Wednesday

The Brussels region has maintained its terror alert at level 4, the highest level possible, Belgian prime minister Charles Michel announced at a government press conference on Monday.

Schools in Brussels will reopen on Wednesday - as will the metro and underground tram system. 

The rest of Belgium will remain on level 3 out of 4, Michel added. The current terror alert level could be kept in place until Monday, but will be reassessed on a daily basis.

Belgium increased the threat level for the Brussels region from 3 to a maximum 4 on Saturday, warning of a "serious and imminent" risk of an attack.

A telephone hotline providing information about the threat level has received more than 17,000 calls since opening on Saturday.

Meanwhile a fourth suspect was charged in Belgium over the Paris terror attacks on Monday, the Belgian federal prosecutor announced.

The man was arrested on Sunday night in a series of co-ordinated police raids around Brussels and Charleroi was charged with belonging to a terrorist group and participating in the Paris attack.

Another 15 people arrested on Sunday were freed without charge. The prosecutor said: "It is not uncommon, during large-scale search operations, to bring in several people merely for thorough questioning or to clarify why they were found on the searched premises."