A car bomb exploded Tuesday near the main Basque city of Bilbao (search) after a warning call purportedly from the armed separatist group ETA (search), and a policeman was slightly wounded, the Interior Ministry said.

The bomb exploded in Getxo, a wealthy town nine miles north of Bilbao, a ministry official in Madrid said.

The explosion occurred after a person claiming to represent ETA called the Basque newspaper Gara, which often serves as a mouthpiece for the group.

One policeman was slightly injured while helping cordon off the area identified by the caller as the target, the Interior Ministry office in Bilbao said.

The bomb destroyed the car carrying it and shattered many nearby windows, TV station Telecinco said, quoting witnesses.

The explosion came amid growing speculation that ETA might call a cease-fire.

On Sunday, ETA issued a statement appealing to the Spanish government to start peace talks with its banned political wing Batasuna (search). But the statement made no mention of ETA laying down its weapons — the government's stated conditions for undertaking such talks.

ETA has claimed or been blamed for more than 800 deaths since the late 1960s in a campaign of bombings and shootings aimed at carving out an independent Basque homeland it territory straddling northern Spain and southwest France.