The Washington Post reports Monday that investigators in Spain now believe Al Qaeda was responsible after all for the Spain bombings:

Investigators believe the train bombings that killed 200 people here last week were the work of a multinational cell of al Qaeda loyalists, some of whom entered Spain specifically to carry out the attacks and who are now the target of an international effort to identify and capture them, according to European and Arab intelligence officials. The officials said the preliminary investigation and interrogation of five arrested suspects -- three Moroccans and two Indian Muslims -- as well as other evidence indicated that the Thursday morning rush-hour bombings were carried out by the al Qaeda network, marking the first time the group has struck in Europe.

The way the bombings were carried out is particularly worrisome to European leaders:

For European leaders, the al Qaeda link is a chilling development, and security services across the continent are now scrambling to assess the likelihood of further attacks in Europe. Analysts said the method of the Madrid attacks -- synchronized bombings apparently carried out by remote control rather than by suicide bombers -- suggested that Islamic extremists had become more adaptable and, therefore, even more of a threat.

The Moroccan suspects are being interrogated. So far, they have provided only limited information and have made several requests for the Koran. As to why Spain was chosen, officials theorize: