DUBROVNIK, Yugoslavia--Tens of thousands of Yugoslavs have spent the last two nights without shelter in the wake of an earthquake Sunday morning.

The quake killed 235 people and injured more than 1000 along the Adriatic coast of Southern Yugoslavia and Albania while destroying buildings along a 60-mile strip of coastline including the resort region of Montenegro.

Officials said yesterday they recorded 150 aftershocks following the first tremor, which measured 6.5 on the Richter scale. There were no reports of foreigners among the dead.

Britain to the Rescue

The British Foreign Office said yesterday it will send $160.000 worth of medical and other supplies to the region in response to an aid request from Yugoslavia.

Drinking water is in short supply in the region because the earthquake destroyed piping systems and sewage has polluted springs. Water trucks have made some deliveries to the area.

Aftershocks and a shortage of medical supplies have hampered rescue efforts. East German and Yugoslav tourists are reportedly vying for airplane tickets to leave the area.

President Tito, who had been vacationing at his residence in the Montenegro region at the time of the earthquake, returned to Belgrade yesterday after touring the disaster area.