Sunday September 7, 2008  1:31 pm

ContentType:Spot Development; ContentElement:FullStory; Breaking:True;

ISLAMABAD, Pakistan (AP) - Two American diplomatic outposts in Pakistan received envelopes containing an unknown white powder last week, sparking a security scare, a U.S. Embassy spokesman said Sunday.

Tests are being conducted on the substance, spokesman Lou Fintor said. He declined comment on whether any embassy staffers had become ill or were under observation.

The envelopes were sent to the U.S. Consulate in Karachi on Thursday and the U.S. Embassy in Islamabad on Friday. Fintor said both facilities have remained open, with no plans to close them.

``Embassy personnel followed established response procedures,'' Fintor said. ``We applaud the rapid and appropriate response by our mailroom and security staff to contain any potential threats. We take threats of this type very seriously, hoax or not.''

He would not say where the envelopes had been mailed from, pending an investigation, or to whom they were addressed.