Belgium Verviers Raid
Verviers police, supported by security forces, contain the area after a raid on a terrorist cell.AFP / Getty Images

The terror alert has been raised to three in Belgium after a successful raid against a suspected terrorist group in the city of Verviers, near Liège.

At a press conference, a member of the Federal Prosecutor's office said the suspects were planning to carry out attacks in Belgium "imminently."

Officials confirmed that two suspects were killed by police after they opened fire for several minutes. One suspect was arrested and is in police custody. No police officers or civilians were injured or killed during the raid.

The exact target for the planned attack has not been confirmed, however there is speculation that the suspects were planning to storm a police station and intended to cause casualties "on a grand scale."

Ten arrest warrants had been issued in a series of coordinated raids targeting recent returnees from Syria, who were under surveillance as part of a major anti-terrorism operation in the capital, Brussels, and in Molenbeek.

The raids also targeted several people who were part of an operation cell, in the eastern town of Verviers, which is 70 miles from Brussels.

"During the investigation we found that this group were about to commit terrorist attacks in Belgium," said the spokesperson for the Federal prosecutor.

Verviers police were aided in the raid by a "special security arm" of the Belgian police force. Belgian magistrate Eric Van der Sypt said the men targeted in the Verviers raid were "extremely well-armed" with automatic weapons.

Describing the scene one witness said: "There were police announcements to clear the area around six o'clock. We could see lots of police vehicles, and officers in balaclavas.

"Most of the police vehicles were in Rue du College, and there were clearly anti-terrorist officers on the street. There were three of four explosions, and then continual gunfire. It was terrifying, but the police brought the situation under control."

Another witness said he saw two young men apparently of North African origin "dressed all in black carrying a bag of the same colour."

There is a heavy police presence in Verviers and several other arrests have also been reported.

The latest planned attack which has been described as "Belgium's Charlie Hebdo," follows three days of violence in nearby France, which left 20 people dead, including three Islamic State and Al Qaeda linked terrorists.

Earlier, Belgian authorities arrested a man suspected of supplying the gunmen, as funerals for the victims of the attacks continued.

It is not the first time Belgium is linked to Islamic extremism. Earlier this week, a notorious figure from the Brussels underworld accused of supplying weapons to the French brothers who carried out the Charlie Hebdo massacre handed himself over to police.

Last year, Mehdi Nemmouche, a French jihadist who fought in Syria, shot dead four people at the Brussels Jewish Museum.

A second press conference regarding the Verviers raid will be held tomorrow (16 January) at 11am.