Belgian police conducted major raids Friday as authorities continue to search for suspects tied to the Tuesday attacks that killed at least 31 people and wounded more than 300 in Brussels. At least three people were arrested in raids across the capital, as authorities begin to unravel the links between the attacks in Belgium and the November attacks in Paris.

Authorities said Friday that Zaventem Airport attacker Najim Laachraoui, 24, made two of the suicide vests used in the Paris attacks, the New York Times reported. The November attacks in Paris left 130 people dead and over 300 wounded.

Days before Tuesday’s attack, Belgian authorities captured Paris attack suspect Salah Abdeslam. Laachraoui, who used an alias, was known to have traveled with Abdeslam. Laachraoui was a citizen of Belgium, and authorities said he traveled to Syria in 2013.

Three of the Brussels attackers died carrying out suicide bombings. Laachraoui and Ibrahim el-Bakraoui, 30, were two of the three attackers at Zaventem Airport. A third airport attacker has not yet been identified. Khalid el-Bakraoui, 27, was the attacker at the Maelbeek Metro Station in the heart of Brussels close to European Union buildings.

Investigators named additional suspects Friday, including Naim al-Hamed, Reuters reported. The 28-year-old Syrian’s name was on a list along with Laachraoui, Khalid el-Bakraoui and Mohamed Abrini. Authorities said they believed al-Hamed had also played a role in the Paris attacks. Abrini, who is currently on the run, is believed to be Abdeslam’s childhood friend, the Guardian reported.

In France, authorities arrested Reda Kriket on Thursday evening. Kriket is suspected of providing financial support to the operatives linked to the Islamic State group, also known as ISIS, in Europe. The three people arrested in raids in Brussels Friday were being questioned about possible connections to Kriket.

Authorities in Germany, the Netherlands and Spain were searching for additional suspects Friday who are believed to be linked to ISIS.

GettyImages-517253288 People gather to pay tribute to the victims of the Brussels attacks on the Place de la Bourse (Beursplein) in central Brussels, on March 24, 2016, two days after a triple bomb attack, which responsibility was claimed by the Islamic State group, hit Brussels' airport and the Maelbeek - Maalbeek subway station, killing 31 people and wounding 300 others. Photo: PHILIPPE HUGUEN/AFP/Getty Images