AlQa'dah 28, 1432, Oct 26, 2011, SPA - Officials warned Wednesday that the swelling river in the densely populated heart of Bangkok could flood the capital in the next couple days, according to a report of the German Press Agency "DPA". Bangkok Governor Sukhumbhand Paribatra said levels of the Chao Phraya River had reached a record high and threatened to overflow. It broke over the banks in several places early Wednesday. Prime Minister Yingluck Shinawatra said flood walls might not hold and the inner zones of the capital could be under water. "The highest risk will be areas along the Chao Phraya River and the floodwalls along the banks," Yingluck said late Tuesday. Vice Admiral Niruth Hongprasert said high tide during the next couple days could raise the river to 2.6 metres above sea level, causing a general breach of the city's inner floodwall. A special holiday is to start Thursday and run through Monday. Yingluck's cabinet ordered the holiday in 21 provinces, including Bangkok, to allow residents to concentrate on the emergency during a high tide period. The Don Muang domestic airport in northern Bangkok was closed Wednesday after water flooded runways. The Suvarnabhumi International Airport east of the city remained open.