Pakistan's Interior Minister says a blacklisted American citizen who entered Pakistan earlier this month has been deported again after being interrogated.

Chaudhry Nisar Ali Khan told the National Assembly on Tuesday that Matthew Barrett, a 33-year-old Alabama native, was first deported in 2011 after being detained near a sensitive military installation. He did not say when Barrett was deported this time.

Pakistan is an ally of Washington in its war on terror, but they have had fraught relations over the years.

Washington has at times blamed Pakistan for not doing enough to combat terrorism, a charge that Pakistan denies.

Islamabad has said Barrett was never suspected of spying, but that he was involved in "wrongdoing." It never explained the charge.