Planes on which the US Central Intelligence Agency (CIA) is suspected of transporting terrorist suspects also landed on Spain's Canary and Balearic Islands, the daily El Pais reported Wednesday.

The report said the secret CIA flights landed at least four times on the Canary island of Tenerife between March 2004 and last May, and once on the Balearic island of Ibiza.

It had earlier been reported that such flights landed in Palma, capital of the Balearic Majorca, 10 times between January 2004 and January 2005.

Spanish Interior Minister Jose Antonio Alonso has said on Tuesday that if the landing on Spanish soil of such flights were confirmed, it could hurt relations between Madrid and Washington.

Using Spanish airports for secret flights to transport terrorist suspects was "a serious and intolerable issue" which could affect "the level of relations between the two governments," said the minister.

Human rights groups say the planes may be used to transport terror suspects for interrogation in places where US rules on torture do not apply.

Source: Xinhua