Tehran, Iran: A senior Iranian official says faulty pumps were deliberately sold to the Islamic Republic but scientists detected the problem before they were put into operation inside a nuclear plant.

Asghar Zarean, in charge of nuclear security at the Atomic Energy Organization of Iran, made the remarks in comments posted Monday on state TV’s news website.

He says the pumps were tampered with by what he described as agents of Western intelligence agencies.

He says the contractor who sold the pumps did not know they were faulty. He did not identify the contractor.

Zarean over the weekend claimed that Iranian authorities thwarted attempted sabotage at the heavy water nuclear reactor at Arak but provided no details.

Tehran says such attacks are part of a concerted sabotage campaign.