Brussels attacks: Media quash reports of Laachraoui arrest

Security has been stepped up round key buildings

Belgian media have retracted reports that a key suspect in the attacks in Brussels has been arrested.

News outlets, quoting judicial sources, had named him as Najim Laachraoui, possibly seen in a CCTV image before the Zaventem airport blasts.

But media later said that a man detained in the district of Anderlecht was not Laachraoui.

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

Two of the other attackers have been named in Belgian media as the brothers Khalid and Brahim el-Bakraoui.

Belgium is observing three days of national mourning and held a minute's silence for the victims at midday (11:00 GMT).

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

More about the attacks

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Brussels attacks: Live updates

What we know so far

Why was Brussels attacked?

Victims and survivors

Eyewitnesses recall explosions

In pictures: Brussels explosions

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