Bengaluru, Torrential rains over the last two-three days caused flash floods in coastal and northern Karnataka, disrupting normal life, as low-lying areas were inundated and roads submerged due to overflowing rivers and tributaries, an official said on Thursday.

"Incessant and widespread rains in coastal and northern regions of the state due to low pressure and strong surface winds wreaked havoc, as flash floods in towns and villages caused hardship to people in low-lying areas and on river banks," a state Natural Disaster Management Authority official told IANS here.

With copious rains in catchment areas filling dams and reservoirs across rivers like Krishna, Tunga, Bhadra, Bhima and Cauvery, the authorities released excess water from them causing flash floods in towns and villages across the coastal, northern and northwest regions.

Bagalokote, Ballari, Belagavi, Bidar, Dharwad, Gadag, Haveri, Hubballi, Kalaburagi, Koppal, Raichur and Yadgir in the state's north and northwest regions were the worst affected.

With the southwest monsoon extending beyond September, excess rains and water-logging in agricultural fields damaged kharif crops before harvesting.

About 5,000 people have been shifted to 36 relief camps in the affected districts from flood-hit villages in both the regions.

Teams of the State and National Disaster Relief Force were deployed in Kalaburagi, Raichur and Yadgir districts to rescue the marooned people and their livestock.

Uttar Kannada, Udupi, Dakshina Kannada and Kodagu districts in the coastal and south interior areas and Shivamogga in Malnad region were lashed with heavy rains up to 19-20 cm over the last 48 hours.

According to the weather office, monsoon was vigorous over coastal and north interior areas and active over south interior parts of the state.

Kollur in Udupi district recorded 22cm rainfall, Hosanagar in Shivamogga district, 21cm, Kottigehara in Chikkamagaluru distirct 17cm, Hunchadakatte in Shivamogga district 16 and Agumbe and Bhatkal in Uttara Kannada district 13 cm each.

The state Meteorological Department has forecast moderate to heavy rains with thundershowers at most places in coastal areas, at many places in the north interior areas and at a few places in south interior parts of the state till Saturday.

As high waves up to 3 metres are forecast till October 18 along the coast from Mangalore to Karwar, with strong surface winds, fishermen have been advised not to venture into the Arabian Sea.