Chinese security officials have detained hundreds of Tibetans in Lhasa following multiple self-immolation protests against the Chinese control over Tibet, a US-based broadcaster reported Thursday.

About 600 Tibetans had been detained since the Sunday's protests in Lhasa in which two Tibetan men set themselves on fire, Radio Free Asia (RFA) reported citing sources who wished to remain anonymous.

The detention came amid news that a Tibetan mother of three set herself on fire outside a monastery in Aba country in the Sichuan province.

Two young men had earlier set themselves ablaze in front of Lhasa's famed Jokhang Temple, Chinese news agency Xinhua reported.

Over 35 Tibetans had set themselves on fire since March 2011 in the deadly protest against the six-decades of Chinese rule over Tibet, killing at least 27, Reuters reported citing Tibetan rights groups.

Chinese police had tightened security in Lhasa city following the self-immolation protests, sources said.

Following the self-immolations, pilgrims from Kham and Amdo (regions located mainly in Sichuan, Qinhai, and Gansu provinces as well as in parts of the Tibet Autonomous Region) are being arbitrarily rounded up, with some being expelled from Lhasa, a Tibetan woman was quoted as saying by RFA.

About 80 Tibetans were detained Sunday and Monday on suspicion of having recorded the protest on their cameras and cell phones, a Tibetan political prisoner in India was cited by RFA.

The detained Tibetans were reportedly being held at the Tsel Gungthang detention center. 

Foreign tourists who were present at the self-immolation site were taken back to their hotels and their cameras were thoroughly searched and some were told to leave Tibet, the RFA report said.

Several rights organizations reported in late February that foreign journalists had been banned from entering Tibet as part of the Chinese efforts to prevent international news organizations from covering Tibetan demonstrations.

A crew from CNN was arrested at a toll barrier in the Sichuan province in the last week of January and was prevented from travelling to neighboring Tibet, Reporters Without Borders (RWB) reported.

China calls these self-immolators terrorists and reportedly released a documentary in mid-May accusing the Dalai Lama of orchestrating a wave of self-immolations by Tibetans.

However, the Tibetan government-in-exile has denied that the Dalai Lama or other exiled Tibetan monks are responsible for inciting the protests.