Spanish police arrested on Tuesday a family of four Moroccans suspected of having links to the Madrid train bombings of last year, the Interior Ministry said.

The four — a married couple in their 40s and their two sons — were arrested in Leganes (search), a suburb of Madrid, the ministry said in a statement.

In the March 11 train attack, a series of backpack bombs went off on the Madrid commuter rain network, killing 191 people and wounding more than 1,500. In videos, militants claimed to have carried out the attack on behalf of Al Qaeda.

The next month, seven suspects in the attack, including several alleged ringleaders, blew themselves up as police closed in.

The Interior Ministry said the four newly detained Moroccans were believed to have helped two other suspects from the train attack flee after the April 3 collective suicide.

The four are also believed to have links to Hasan al-Haski (search), a 41-year-old Moroccan arrested in the Canary Islands in December, the ministry said.

Al-Haski is suspected of helping prepare the Madrid bombings and of being a prominent member of the Moroccan Islamic Combatant Group (search), an Islamic organization believed tied to Al Qaeda blamed for 2003 bombings in Casablanca attacks that killed 45 people, said Juan del Olmo, the judge leading the March 11 probe said.