Rockingham's Lake Richmond set alight

Authorities are hunting for a suspected arsonist after a number of fires were lit at Lake Richmond in Rockingham.

Firefighters were called to the lake after receiving a number of triple zero calls around 3pm on Tuesday reporting smoke and flames.

It took them an hour to extinguish the fires.

Police are treating the fires as suspicious and are urging anyone with information, or who saw any suspicious activity in the are at the time, to contact Crime Stoppers on 1800 333 000 or via www.crimestopperswa.com.au

Rewards of up to $25,000 are available for information that leads to the identification and conviction of an arsonist.