ETA OR AL-QAEDA?….The Spanish Interior Minister thinks the evidence is mounting that ETA was reponsible for Thursday’s bombing, not al-Qaeda:

[Angel] Acebes said the bombs consisted of satchels filled with 20 to 30 pounds of dynamite, set off by a cell phone. He said the dynamite chemically matched 1,100 pounds of explosives seized in February from an ETA van heading toward Madrid, and that the satchel and cell phone setup matched that found on two ETA members when they were arrested at a northern Madrid commuter rail station on Christmas Eve.

….Asa Hutchinson, the [U.S.] Homeland Security Department’s undersecretary of borders and transportation, said American intelligence agencies had detected no spike in “chatter” among al-Qaida-related groups before the attacks. Other U.S. officials stressed that the group that claimed responsibility for the bombings, the Abu Hafs al Masri Brigades, is thought to exist in name only and has made implausible claims of responsibility before.

….Interior Minister Acebes was adamant that the evidence pointed to ETA. He noted that ETA has a history of creating havoc in the days before a national election.

He also said the explosives used – Goma II Eco – were made in Spain and that ETA had used the same brand in previous attacks.

But the same article also summarizes the evidence favoring al-Qaeda involvement:

A caller claiming to represent ETA denied that the group had been involved in the attack. Journalists here said ETA never had rejected responsibility for an attack before.

….Many Spaniards, particularly those who support the Socialist Party in Sunday’s elections, suggested that Aznar’s government might not be willing to disclose an al-Qaida link until after the vote, for fear of hurting the chances of Aznar’s Populist Party holding on to power.

“Listen, ETA has never done a bombing like this without calling and warning the government beforehand,” said Olga Gonzalez, a 32-year-old secretary. “Ninety percent of Spaniards were against the war in Iraq. If al-Qaida is involved and not ETA, this changes everything for the elections. It will only help to elect the Socialist Party.”

In other words, we still don’t know.

UPDATE: The New York Times has more here, including a statement from a Spanish antiterrorism official that Goma II has been linked to ETA “only rarely” since the 1980s.