By Nate Raymond

NEW YORK (Reuters) - Federal prosecutors on Thursday brought additional charges against two New York City women accused of planning to carry out an explosive attack in the United States.

Noelle Velentzas, 28, and Asia Siddiqui, 31, were formally indicted by a federal grand jury in Brooklyn, New York, a month after their arrest on a charge of conspiring to use a weapon of mass destruction.

The indictment goes beyond that count to charge the women additionally with teaching and distributing information pertaining to the making and use of a weapon of mass destruction.

Siddiqui was also hit with a third charge of making material false statements to the FBI in July by saying she had not contributed writings to jihadist magazines or been in contact with a member of al Qaeda in the Arabian Peninsula.

Lawyers for the women did not immediately respond to requests for comment.

Prosecutors have previously said that the women, former roommates in the city borough of Queens, had plotted to hit police, government or military targets based on their "violent jihadist beliefs."

Authorities said the women had researched how to build an explosive device. When they were arrested, agents found bomb-building materials including propane gas tanks, soldering tools, pipes, a pressure cooker and fertilizer, authorities said.

A criminal complaint unveiled at the time of their arrest said Velentzas had praised al Qaeda's Sept. 11, 2001, attacks on the United States and said she and Siddiqui were "citizens of the Islamic State."

The women face the possibility of life in prison if convicted.

(Reporting by Nate Raymond in New York; Editing by Frances Kerry)