DUBAI, 23, April— Five laborers died and seven more were hurt when the dome of a public building under construction collapsed on them in the Gulf emirate of Sharjah, police said yesterday.

Iron scaffolding caved in Sunday when tons of cement was being poured into the dome of the $3-million Sharjah Town Planning Department.

The casualties, three of whom were gravely injured, were Egyptian, Indian and Pakistani, police chief Col. Saleh Ali Al-Mutawee told AFP.

The police chief attributed the cause of the accident to poor support from the steel framework prepared for pouring the cement. He announced that all those responsible for the construction would be placed in custody until an inquiry was completed to determine the exact causes of the accident.

Frantic rescue efforts were made to save the workers trapped under the mound of rapidly hardening cement.

The workers were buried when the intricate scaffolding collapsed as 40 cubic meters of cement was tipped on to it on the building site at Al-Liyyah.

They plunged 15 meters to the ground and the wet cement and steel bars cascaded on top of them. Until late in the evening, rescue teams toiled in vain to reach three workers trapped under the debris.

During the afternoon they were able to see and talk to two of the three entombed men — but by late evening police announced that they had died.

Rescue work was continuing into the early hours of yesterday, as teams were unable to pinpoint the location of the third man under the debris.

Rescue workers had to remove all the intact scaffolding and steel supports from the huge room to get to the cement, which was hardening fast, and to remove the tangled web of steel bars which had collapsed.

Col. Al-Mutawee told the Gulf News newspaper that his department was notified of the accident at 12.35 p.m. and police teams reached the spot within 10 minutes.

“Some of the workers had half their bodies stuck in the cement and between the steel bars. Others were buried under the debris,” he said.

Doctors were rushed to the site to give some of the trapped workers anaesthetic while they were being cut out of the mangled wreckage.

Sharjah police sought the help of Dubai police and the Civil Defense Department in Sharjah to help rescue as many workers as possible before the cement hardened.

Brake failure caused Oman bus crash: Mechanical failure was the cause of the horrific accident that resulted in the death of 46 construction workers when a bus fell into a deep ravine near Salalah, southern Oman, last Friday, according to four survivors.

The four Indians said they owed their escape to the driver Mohammed Rafi, who shouted as the brakes failed. The four immediately jumped out of the packed bus along with two Omanis.

The driver tried to reduce the speed by shifting the gear but his efforts went in vain, the Gulf News quoted them as telling an Indian Embassy official.