With seasonal showers battering Bangladesh for the fourth straight day Wednesday, the flood death toll rose to 23, officials said. Five bodies were plucked from Jamuna river after a small boat sank overnight in swift currents, raising the death toll from flood related causes to 23 in the past four days. More than 500 fishermen, who had defied warnings of squalls and high waves in the Bay of Bengal, remained missing since early Tuesday, according to the sea trawlers association in the southern town of Coxs Bazar. The late monsoon downpours triggered by a low in the bay dumped a record 580 millimetres of rain on Dhaka since the weekend, and flooded the central and southern regions of Bangladesh. Dhaka, the capital city of 10 million residents, was still submerged Wednesday, with boats plying the Motijheel area, the heart of the capital's business district and fishermen casting nets. A local TV news channel showed a man proudly displaying a catfish weighing 5 kilogrammes which he had netted from a flooded road at the center of Dhaka. The National Flood Forecasting and Warning Center said Bangladesh's previous record of 274 millimetres of rainfall in 1966 pales in comparison to the current unbroken spell. The Met Office said the weather system was moving slowly across bordering India's West Bengal state. The earlier deaths included fatalities due to ferry mishaps, mudslides and electrocution.