Belgian police have discovered the body of a woman in a shed belonging to the gunman who went on a rampage, killing four people and himself.
The attack on Christmas shoppers was launched with guns and hand grenades in a busy marketplace in Liege.
People in the town have been expressing their shock after five people were killed, including an 18-month-old toddler, and 122 were wounded.
Summoned for questioning by Belgian police, a man with a history of weapons and drug offences left home armed with hand grenades, a revolver and an assault rifle.
Stopping at a central square filled with holiday shoppers, he lobbed three grenades into the crowd, then opened fire.
Authorities said the gunman also died, but they were at a loss to explain the reason for the onslaught.
The prime minister said it was not related to terrorism.
The midday attack sent hundreds of panicked shoppers stampeding down the cobbled streets of the old city, fleeing explosions and bullets.
"At the beginning, we did not know if there was one, two, three, four, or five of them," one Liege resident said on Wednesday morning.
"Everything was confused. My mum was trapped in a coffee shop and I went there to take her home. Then at Mediacity I've heard that there were some mail bombs. Now we know that it was just one person, but anyway, I don't understand."
Belgian authorities identified the gunman as Nordine Amrani, a 33-year-old Liege resident who had been jailed for offences involving guns and drugs, and had been called in for questioning on Tuesday in a sexual abuse case.
Officials said Amrani left his home with a backpack, armed with hand grenades, a revolver and an FAL assault rifle.
He walked alone to the busy Place Saint-Lambert, the central entry point to downtown shopping streets, then climbed onto an overpass that gave him an ideal view of the square, which was bedecked with a huge Christmas tree and crowded with shoppers.
From there, Amrani lobbed three hand grenades towards a central bus stop, which serves 1,800 buses a day, and opened fire.
The explosions sent shards of glass from the bus shelter across a wide area.
Hundreds fled the square as well as a nearby Christmas market. Video showed people, including a large group of preschoolers, rushing to seek cover, some still carrying shopping bags.
"I am shocked like everybody. No human being should act like this," another local man said on Wednesday morning.
Amrani died at the scene, but Liege Prosecutor Danielle Reynders told reporters he was not killed by police.
It was unclear if he committed suicide or died by accident, though he still had a number of grenades with him.
Those killed were two boys ages 15 and 17, a 75-year-old woman, and an 18-month-old toddler who died on Tuesday evening in hospital, Liege police said.
APTN / 3 News