DUBAI (Reuters) - A Saudi court has jailed 21 people, including at least one government official, after houses were built on flood-prone land, leading to more than 100 deaths by drowning, local media reported on Thursday.

The rulings came nearly a year after two men were jailed in one of the first convictions in a graft crackdown the government launched following the floods hit Jeddah in 2009 and 2011.

Arab News daily reported that a senior municipal official was sentenced to five years in prison and fined 700,000 riyals ($186,700) for giving permission for people to buy and build houses in areas hit by the floods.

Houses were built on low-lying land and the situation was made worse by the absence of a city-wide drainage system. The floods spread after just a few hours of torrential downpour in an arid region where months often go by without any rain at all.

The newspaper, quoting judicial sources, said the indicted included real estate developers and businessmen, adding that charges included bribery.

King Abdullah ordered an investigation into corrupt practices linked to the floods in 2009.

Saudi Arabia is a monarchy with no elected parliament and little tolerance for public dissent. Most senior government positions are occupied by high ranking royals, some of whom have major business interests. ($1 = 3.7503 Saudi riyals)

(Reporting by Mahmoud Habboush; Editing by Jason Webb)