Thursday May 28 3:51 PM EDT
KATHY GANNON Associated Press Writer
ISLAMABAD, Pakistan (AP) - Just hours after Pakistan detonates five nuclear devices, Pakistan's President Rafiq Tarar on Thursday declared a state of emergency citing ``threat by the external aggression to the security of Pakistan,'' the state-run news agency reported.
The terse announcement does not identify who the aggressor might be but Pakistan has accused neighboring India of threatening to attack its nuclear installations.
A state of emergency suspends Pakistan's constitution and the legal system.
Pakistan earlier tested five nuclear devices in response to the testing two weeks ago by India of five nuclear devices.
The retaliatory tests virtually guarantee a nuclear arms race on the Asian subcontinent, one of the poorest regions in the world.
Shortly after midnight on Thursday India's ambassador to Pakistan was summoned to the foreign ministry and warned that Pakistan had received ``credible evidence'' of a possible pre-emptive strike by India on its nuclear facilities.
India has called the allegations ``baseless and malicious''.
Pakistan warned India of ``massive retaliation'' if it attacked them.
The Indian ambassador was ``c1early told that any attack on our nuclear facilities would be in violation of our existing agreement against attack on such facilities,'' a foreign ministry statement issued earlier Thursday said.
``Any such act would warrant a swift and massive retaliation with unforeseen consequences,'' it said.
Pakistan's military has confirmed its troops are on alert at nuclear installations around the country.
Late Wednesday, U.S.-made F-16 fighter jets and army helicopters were on patrol over the Kahuta nuclear research station, 40 kilometers (25 miles) east of Islamabad. Kahuta is where it is believed Pakistan conducted the bulk of its nuclear research and uranium enrichment program.
Other major nuclear sites include the Pakistan Institute of Science and Technology, about 25 kilometers (15 miles) east of Islamabad, and Golra, believed to be an extension of the Kahuta plant, which is 50 kilometers (30 miles) west of the capital.
The Khushab nuclear reactor, about 200 kilometers (120 miles) northeast of Islamabad in Punjab province, is believed to produce enough plutonium to manufacture between one and two nuclear weapons annually.
Nearby in Chashma, Chinese contractors are building a 300 megawatt nuclear power plant.
Pakistan and India have fought three wars since 1947 and came dangerously close to a fourth, possibly nuclear, confrontation in 1990 over the disputed state of Kashmir.
Roughly 25 percent of Pakistan's dlrs 13 billion budget goes toward defense spending. India and Pakistan are among the world's leading purchasers of military equipment.