Police have carried out a series of raids across Belgium after bombs exploded at Brussels airport and in the city's subway system, killing at least 31 people.
A nail-filled bomb, chemical products and an Islamic State flag were found during a house search in the Schaerbeek neighbourhood as police hunted one of three suspected airport bombers who remained at large.
The airport blasts, in which two suicide bombers are believed to have died, left behind a chaotic scene of splattered blood in the departure lounge as windows were blown out, ceilings collapsed and travellers streamed out of the smoky building.
About an hour later, another bomb exploded on a rush-hour subway train near the European Union headquarters. Terrified passengers had to evacuate through darkened tunnels to safety.
Belgium raised its terror alert to the highest level, diverting planes and trains and ordering people to stay where they were for most of the workday.
Authorities also released a photo taken from closed-circuit TV of three men pushing luggage carts, saying two of them apparently were the suicide bombers and that the third - dressed in a light-coloured coat, black hat and glasses - was at large. They urged the public to contact them if they recognised him.
Airports across Europe - and in the New York area - tightened security.
The Islamic State group claimed responsibility for the Brussels attacks, saying in a post on the group's Amaq news agency that its extremists opened fire in the airport and "several of them" detonated suicide belts. It said another suicide attacker struck in the subway.
Authorities found and neutralised a third bomb at the airport once the chaos after the two initial blasts had eased, said Florence Muls, a spokeswoman for the airport.
Mr Michel said there was no immediate evidence linking the attacks with Abdeslam. After his arrest, Abdeslam told authorities he had created a new network and was planning new attacks.
Belgian Health Minister Maggie de Block said 11 people were killed and 81 wounded. Eleven people had serious injuries, Marc Decramer of the Gasthuisberg hospital in Leuven told broadcaster VTM. The nails apparently came from one of the bombs.
The airport was ordered closed for the rest of the day and CEO Arnaud Feist said the facility would be closed at least through Wednesday. About 600 flights in or out of Brussels were diverted or cancelled, Mr Muls said.
The metro also was ordered closed as the city was locked down. By the end of the workday, city officials said residents could begin moving around on the streets of the capital and train stations were reopening. But Peter Mertens of the Belgian crisis centre said the threat of more attacks "is still real and serious".
At least one and possibly two Kalashnikovs were found in the departure lounge at the airport, according to a European security official.