WASHINGTON — President Reagan, expressing "concern and anger," today pledged a thorough investigation of the Iraqi missile attack that killed 28 servicemen aboard the Navy frigate Stark in the Persian Gulf. Pentagon officials said it did not appear that the ship tried to shoot down either the attacking plane or its missile despite at least a minute's warning.
Vice Adm. Henry C. Mustin, a deputy chief of naval operations, called the incident "a sudden and unprovoked attack."
He also acknowledged that the frigate was equipped with weaponry that could have been used against the missile or plane but said no defensive action was apparently taken.
Mustin stressed that he was not in a position to assess at this point what happened aboard the ship immediately before the attack.
"We were in international waters, not a war zone," Mustin said.
In remarks at a White House ceremony, Reagan said: "We have protested this attack in the strongest terms and we are investigating the circumstances of the incident.
"I share the sense of concern and anger that Americans feel over yesterday's tragedy."
Reagan said he would report to the American people as soon as the facts are assembled. He said he would spell out "any further steps that are warranted."
Presidential spokesman Marlin Fitzwater said Iraq's ambassador, Nizar Hamdoon, "has expressed profound regret that this occurred and pledged a complete investigation."
At the Pentagon, Mustin and Lt. Gen. Richard A. Burpee said the air strike occurred at about 10:10 p.m. in an area about 60 miles south of two earlier attacks Sunday by Iraqi warplanes against commercial ships. Mustin said the ship knew that it had been "locked on" by the warplane's radar--a prelude to attack--and that the Stark attempted twice by radio to warn the attacker that it was an American ship. He said it was not known whether the message was received.
Burpee said it was unclear whether the Stark had been attacked by one plane or two. He said the captain of the ship had now reported being struck by two missiles, although earlier reports had suggested only one missile struck the frigate.
The Stark is equipped with an automatic defense system designed to counter missile attacks, but the system is routinely shut off for safety reasons during peacetime steaming, a senior Navy officer said.
Capt. W. Lewis Glenn, captain of the battleship New Jersey, told reporters in New Jersey that the system uses radar to detect incoming missiles and then fires 150-round bursts of 20-millimeter depleted uranium bullets at the target. Uranium is not used for its radioactivity but for its heavy throw weight. The radar system guides the bullets to the incoming target, detonating the missile a safe distance from the ship, Glenn said.
A Pentagon official who demanded anonymity said a small warship such as the Stark in wartime would use surface-to-air missiles to shoot down any plane before it drew near enough to fire.
"We were not at war. The ship had no reason to expect an attack from an Iraqi plane," this official said.
Mustin and Burpee also revealed at the afternoon briefing:
--The death count from the attack rose to 28, but the Pentagon was not yet prepared to say all men aboard the ship have been accounted for.
--The crew of the Stark was fighting fires and attempting to handle the flooding caused by fighting the fires. Mustin said much of the interior remains full of smoke and the ship's phone and loudspeaker systems have been disabled.