Bangkok residents were fleeing the capital Thursday after authorities called an emergency five-day holiday and urged people in flood-prone parts of the city to leave to avoid a massive deluge. Flood waters were already seeping into central parts of Bangkok in the morning, with waters entering the iconic Grand Palace, near the Chao Phraya river, an AFP photographer said. After days of preparing for the onslaught of water, many citizens abandoned their homes on Wednesday night and Thursday morning and were heading to safety in other areas, especially southern beach towns of Hua Hin, Phuket and Pattaya. "We have learned that all of these destinations are packed with Thais who have moved from Bangkok," said the Tourism Authority of Thailand (TAT) deputy chief Sansern Ngaorungsi. He said domestic flights from the country's main air hub, Suvarnabhumi -- which is still operating as normal -- were also "very, very packed". Televised footage showed crowded bus terminals in the capital as people sought to escape, while officials said Bangkok's main train station was also filling up and roads north and east out of the city were choked. "Traffic congestion to Pattaya in (southeastern) Chonburi province began on Wednesday evening," Major General Norraboon Nanna, commander of the highway police, told AFP by telephone. Government offices were shut across the capital on Thursday after the government has ordered a five-day holiday for 21 provinces including Bangkok, to allow the city's residents to prepare for the inundation or leave. A huge runoff from the north equivalent to 480,000 Olympic swimming pools is expected to reach the capital at the same time as seasonal high tides this weekend, the UN's Office for the Coordination of Humanitarian Affairs said. Districts north of the centre have already been inundated, shutting down the city's second biggest airport. The country's Flood Relief Operations Centre (FROC), said late Wednesday that it was working on providing extra shelters outside the city of 12 million people, where food and deliveries were expected to become more difficult. "I would like to ask Bangkok people who are already affected or could be affected soon to consider evacuating to other places," said Thongthong Chantarangsu, a spokesman for FROC.