Panaji/Marago - - A series of mysterious blasts that were heard but not seen had South Goa in a tizzy and sparked off speculation about the nature and origin of the explosions on Thursday. Sources said the blasts occurred thrice in succession at around 12:30pm and the origin could be somewhere in Goa's southernmost taluka of Canacona.

The meteorology department in Panaji noted the "disturbance" on its seismograph but said it could not determine its direction or origin.

Quepem sub-divisional police officer R K Patre said he scouted various beach stretches in Canacona, but could not find any trace of a blast. Patre said he also got in touch with the police in Karwar and was told that they too had heard the bang. It is learnt that the noise thundered in Cuncolim and some even in Navelim and Colva claim to have heard it.

A few houses in Mudgeri and Bawal villages of Karwar, near Goa's southern border with Karnataka, were reported to have suffered damage following the "blasts". Reports reaching Panaji said some fishermen from Karwar had seen an aircraft drop something in the sea around noon.

Navy officials in New Delhi denied there was any exercise in the area. Vasco-based navy PRO M C Joshi also denied that any experiments.

"Indian Navy always gives warning to fishermen and mariners before doing any tests so that mariners are well clear of the area," he said.

Confirming the "disturbance", meteorology department director K V Singh said, "There was no tremor, but there were some recurring disturbances like some blast noises. It was not just once, but a number of times. It is, however, difficult to analyze them." He said such disturbances are recorded daily and they vary, but on Thursday, within an hour, there was a series of sounds, after about every five minutes.

The meteorology department in Panaji recorded 'disturbances' caused by a mysterious 'blast' on Thursday. ''However, the direction and distance cannot be analyzed, but these are not earthquakes,'' met director K V Singh said. Two of the three components--east-west component and north-south component-indicate the distance and origin of sound, but the seismograph showed only the Zcomponent-disturbance.

Coast guard officials said the crew on their vessel cruising about four miles in the area between Karwar and Canacona did not hear any sound.

Coast guard DIG M S Dangui said, ''Our men did not hear any sound. Local fishermen said nothing happened, but that they heard some loud sounds.''

Stating that they have ruled out that it was from a ship, Dangui said the coast guard had received information around 1.30pm regarding the blast-like sounds. ''The coast guard ship C 133 was in the area for three hours, but could not discover anything,'' he said.

Efforts to contact the naval base Sea Bird proved futile.