There was not a single reported criminal incident against a mountain user in the areas where the forum was active between October 2011 and January, spokeswoman Merle Collins said in a statement.

The number of crimes against mountain users had dropped 50 percent between 2011 and 2012, she said.

However, The Cape Times reported last Friday that there were 21 attacks on 70 people in 2007, 10 attacks in 2009, and 38 in 2011, with five attacks on Table Mountain, in Cape Town, so far this year.

"As much as we watch them, they watch us. As soon as they see that observation posts are not being manned, they move back in," Andre van Schalkwyk, of Table Mountain Watch, told the newspaper.

He was speaking after a meeting of bodies representing hikers and bikers about crime trends and ways of improving safety.

According to the newspaper, Rhodes Memorial, Devil's Peak, Lion's Head and Signal Hill were hotspots for criminals.

It was reportedly agreed at the meeting that increasing the use of the mountain range would make it harder for criminals to move around and operate without being detected.

On Sunday, SANParks said the forum, which was established after a spate of attacks in 2011, had been active in the City Bowl, from Signal Hill to Devil's Peak and Camps Bay.

Collins said only three incidents of robbery and attempted robbery had been reported between January and February, and that the forum had responded immediately by increasing its activities.

"The primary incidences are thefts and attempted thefts from vehicles left for long periods in parking lots near popular mountain trails."

She warned mountain users not to leave any valuables in their vehicles and to report any suspicious activities.