Police secure an area in Brussels where terrorism suspects were arrested. (Geert Vanden Wijngaert/AP)

The terrorists who carried out the March 22 attacks on the Brussels airport and metro initially planned an attack on France instead, the Belgian federal prosecutor announced Sunday.

A cell of terrorists affiliated with the Islamic State largely conceived and executed November’s attacks on Paris from the Belgian capital, where many of them were reared. According to the prosecutor’s office, members of this cell were apparently “surprised by the speed of the progress in the ongoing investigation” and decided to attack locally instead.

Despite the “speed” of that investigation, though, the terrorists — some of whom were known to the Belgian government — were able to kill 32 people and injure hundreds more in an impromptu operation four months after attacks that killed 130 in Paris.

The Brussels attack came four days after the arrest of Salah Abdeslam, a principal suspect in the logistics behind the Paris assault. Sunday’s revelations confirm what many suspected: Arrests in the days before the Brussels attacks prompted a quick and desperate terrorist retaliation.

Exact details of the abandoned French attack remain unclear, and prosecutors declined to give further information.

Sunday’s announcement came two days after Belgian authorities arrested Mohamed Abrini and three other suspects, all of whom were charged with participating in “terrorist murder” and the “activities of a terrorist group.”

Abrini, a 31-year-old Belgian citizen of Moroccan origin, is a link between the Paris and Brussels attacks, one of many that investigators have uncovered in recent weeks.

Surveillance footage has identified him as the driver of a rented vehicle that transported terrorists back and forth across the French-Belgian border in the days before the Paris attacks. On Saturday, he admitted to police that he was the “man in the hat” at Brussels Airport in Zaventem, walking beside two accomplices who detonated suicide bombs March 22 inside the terminal.

Further footage from the morning of the attack shows Abrini walking out of the airport toward the city, where he remained at large until Friday.

His testimony could provide further insight into the network that planned attacks in Paris and Brussels. The extent to which that network remains active is unknown.