3 Arrested in Brussels in Connection With Paris Raid Arrests were in the areas of Saint Gilles, Rue de Belgrade and Avenue Rogier.

 -- Three people were arrested in Brussels this morning in a series of raids related to an arrest in a Paris suburb Thursday night, the Belgian federal prosecutor said today.

Authorities made the arrests in the areas of Saint Gilles, Rue de Belgrade and Avenue Rogier, the prosecutor said.

Two of the suspects suffered leg injuries, he said, and a police source told ABC News one of those arrested appeared to have been shot.

Two of those arrested were identified as Tawfik A. and Salah A. by the Belgium federal prosecutor's office. The third was not immediately identified.

The prosecutor said the arrests related to a raid in Argenteuil, France, Thursday night that resulted in the apprehension of Reda Kriket, a French national linked to the ringleader of the deadly November Paris attacks.

Kriket was wanted by authorities after he was charged in abstentia in Belgium last summer for his alleged activity to recruit jihadists.

Today's arrests in Brussels followed the detainment of several people in the city last night amid an ongoing manhunt for two suspects in this week's deadly bombings. All but two of those people have been released.

Authorities are looking for a man seen on surveillance video at the Brussels airport prior to the attacks and a man linked to the bombing of the metro station. Officials have not identified either suspect, but a U.S. official said the man seen at the airport was already in U.S. terrorism databases at the time of the attacks.

The Belgian federal prosecutor today confirmed that DNA from one of the dead airport bombers -- 24-year-old Najim Laachraoui -- was found on explosive vests used in the Bataclan and Stade de France attacks in Paris Nov. 13.

The prosecutor said Laachraoui traveled to Syria in 2013. Laachraoui then used a fake alias and traveled with Paris attack suspect Salah Abdeslam in September, the prosecutor said. The two were stopped on the Hungary-Austria border at the time.

Laachraoui then used the false identity to rent a house that was raided in late November, according to the prosecutor.

Hours after Tuesday's attacks, the Syria-based terrorist group ISIS claimed responsibility. In a video released today by an ISIS province in Iraq, two purported Belgian members of the group threaten further carnage. One of the men says in the video, "after New York and Paris, today we declare to you the new 9/11".

On Thursday Belgium lowered its threat level from the highest level, 4, to a 3. Paul Van Tieghem, director of the office that evaluates threats to the nation, said there was no indication that another attack was imminent but that the threat was still serious and possible.

Random checks at metro stations will continue as the subway system gradually reopens with an increased police and military presence in place.

The Brussels airport will not have passenger flights until Sunday.

At least two Americans died in this week's terror attacks in Brussels, a U.S. official said today as U.S. Secretary of State John Kerry was meeting with leaders in Belgium.

The official and Kerry didn't identify the two Americans, who were among at least 31 killed in the attacks.

Andre Adam, a former ambassador to the U.S. during the Clinton administration, was also among those killed, the Belgian Foreign Ministry said today.

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