Abdeslam's elder brother was among the suicide bombers in the November attacks in Paris.

Two explosions were heard Friday evening in the same Brussels neighbourhood, The Associated Press reported.

The deputy mayor of the Brussels neighbourhood of Molenbeek earlier told AP that police were still searching for one person who was holed up in a house.

This undated file photo provided by the Belgian Federal Police shows Salah Abdeslam, who is wanted in connection with recent attacks in Paris. (Belgian Federal Police/Associated Press)

Several exchanges of gunfire rang out in the city's Molenbeek area — the scene of past investigations — and police officers were seen surrounding an apartment block there.

Television footage showed masked, black-clad security forces guarding a street. Reporters at the scene described white smoke rising from a rooftop and a helicopter hovering overhead.

A police spokeswoman said an operation was ongoing and could not give further details.

The mayor of Paris congratulated police on Twitter.

Félicitations aux forces de l'ordre qui ont permis l'arrestation de Salah Abdeslam, au cours d'une opération policière à Bruxelles
— @Anne_Hidalgo
"Congratulations to the police which led to the arrest of Salah Abdeslam, during a police operation in Brussels," Anne Hidalgo wrote in French.

Gwendolyn Rutten, of Belgium's federal liberal party, tweeted: "Strong. We've got him. Bravo to the whole team and [Belgian Prime Minister] @CharlesMichel [Belgian federal police] @FedPol_pers."

Sterk. We hebben hem. Bravo aan de hele ploeg @CharlesMichel en @FedPol_pers
— @RuttenGwendolyn
Belgian police had found fingerprints belonging to Abdeslam at the scene of an apartment raided on Tuesday, prosecutors said earlier.

The Belgian federal prosecutor's office also said an Algerian killed during that earlier operation was probably one of the people French and Belgian investigators were seeking in relation to the ISIS attacks in Paris on Nov. 13.

Police raided an apartment block near central Brussels, Belgium on Friday, March 18. (CBC News)

Public broadcaster RTBF said it had information that Abdeslam, whose elder brother blew himself up in Paris, was "more than likely" one of two men who police have said evaded capture at the scene before a sniper shot dead 35-year-old Belkaid as he aimed a Kalashnikov.

A man named Samir Bouzid has been sought since December when police issued CCTV pictures of him wiring cash from Brussels two days after the Paris attacks to a woman who was then killed in a shootout with police in the Paris suburb of Saint-Denis.

She was a cousin of Abdelhamid Abaaoud, a Belgian who had fought in Syria and is suspected of being a prime organiser of the attacks in which 130 people were killed. Both died in the apartment in Saint-Denis on Nov. 18.

A French police officer inspects an apartment raided by French Police special forces in Saint-Denis, France, on November 18, 2015. (Gonzalo Fuentes/Reuters)

France's BFM television said the fingerprints were found on a glass in the apartment, where four police officers, including a Frenchwoman, were wounded when a hail of automatic gunfire hit them through the front door as they arrived for what officials said they had expected to be a relatively routine search.

Investigators believe much of the planning and preparation for the November bombing and shooting rampage in Paris was conducted in Brussels by young French and Belgian nationals, some of whom fought in Syria for ISIS.

The attack strained relations between Brussels and Paris, with French officials suggesting Belgium was lax in monitoring the activities of hundreds of militants returned from Syria.

Brussels, headquarters of the European Union as well as Western military alliance NATO, was entirely locked down for days after the Paris attacks for fear of a major incident there. Brussels has maintained a high state of security alert since then, with military patrols a regular sight.

With files from The Associated Press
Thomson Reuters, 2016