Two allied F-15s Thursday shot down two more Iraqi planes fleeing to Iran, and a Navy warplane and an Army helicopter have crashed, U.S. military officials said.

Earlier, U.S. officials said Iraq was moving anti-aircraft guns into civilian neighborhoods in Baghdad and Kuwait City to deter allied strikes against the defensive weapons.The officials said none of the gun positions had been attacked but added that the matter was under study by Gen. H. Norman Schwarzkopf, commander of U.S. forces in the gulf.

At a briefing Thursday, Marine Brig. Gen. Richard Neal said two Iraqi Su-22s, and perhaps three, were shot down while flying to Iran. He said four other Iraqi planes were downed Wednesday and credited American pilots with double kills.

He said 134 Iraqi planes - 109 fighters and 25 transports - were believed to have reached safe haven in Iran since the start of the Persian Gulf war.

Tehran television reported Thursday that five Iraqi warplanes crashed after fleeing into Iran and a sixth landed safely. One pilot was killed, according to the Iranian broadcast monitored in Cyprus.

The U.S. military command also reported that the battleship USS Wisconsin fired 11 rounds at targets in Kuwait. It was the first time its guns were fired in conflict since the Korean War, Neal said.

The Wisconsin had previously fired its long-range Tomahawk cruise missiles at Iraqi targets. Its 16-inch guns took out an Iraqi artillery position in Kuwait, Neal said.

The Wisconsin's sister ship, the USS Missouri, had fired its big guns for three days in a row. The Missouri pulled back as the Wisconsin took over the gunnery but remains in the gulf.

The command said two Iraqi MiG-21 fighters listed Wednesday as "probably" shot down by Air Force F-15s had been confirmed. The two were attacked while trying to make a low-altitude escape into Iran. Two other planes, both Su-25s, also were destroyed in the ambush.

It raised the score in aerial combat since the war began to 35-0 in favor of the allies, according to an unofficial tabulation.

On Capitol Hill, just before he and Defense Secretary Dick Cheney were to leave for Saudi Arabia, Gen. Colin Powell, chairman of the Joint Chiefs, said while the damage to Iraqi forces is hard to measure, the losses "appear to have been extensive."

But he cautioned members of the House Armed Services Committee that the probing attacks Iraq has mounted recently demonstrate that "the fight is far from over."

"Our opponent is resourceful and adaptive and still possesses an enormous army," Powell said. "The Iraqis are feeling the effects of our combat power, but we do not delude ourselves that they will give up overnight.

"We must continue to be patient, to accomplish our objectives, and we must not allow Iraq to draw us into fighting the war on its terms," Powell said.

Lt. Gen. Peter de la Billiere, commander of British forces, said, "There is no indication that the Iraqi army will crack in the near future."

The Los Angeles Times reported that more than a quarter of the positions in Iraq's regular army in Kuwait were either deserted or unmanned. The report, quoting allied officials who have questioned Iraqi defectors in Saudi Arabia, said this raised serious questions about Iraq's ability to withstand a ground attack.