where Xi Jinping was named as the organisation's general secretary in a 10-yearly power handover.
The incidents on Sunday and Monday -- in which at least three of the protesters died -- came as authorities in a Tibetan area of Qinghai province apparently fueled anger by issuing school booklets ridiculing the acts, London-based Free Tibet said in a statement.
"We are now receiving reports of self-immolation protests on an almost daily basis," Free Tibet director Stephanie Brigden said.
"Allied to the many other forms of protests which Tibetans are undertaking -- marching, leafleting, displaying banned images and exerting Tibetan culture -- it forms an unimpeachable argument for an end to Chinese occupation."
According to the US-based Radio Free Tibet, the latest incidents -- two in Gansu province, one in Qinghai and one in Sichuan -- brought the number to 21 in November and 85 since 2009.
Three of the latest victims, all in their teens or early 20s, died and one person was taken away by police and his condition was currently unknown, the report said.
Most of the 85 acts of protests have resulted in death, rights groups said.
Up to 20 Tibetan students in Qinghai, in northwestern China, were also hospitalised after police and security forces arrived at a protest apparently over the school booklets on Monday, Free Tibet said.
As many as 1,000 students from the school in Chabcha county took part, it added.
"Although we cannot confirm whether security forces beat students or not, it would appear that the change in Chinese leadership has not led to a change in the brutality which passes for government in Tibet," Brigden said in a reference to the Communist Party power handover.
One Tibetan in Chabcha county confirmed to AFP by phone that there was a protest on Monday, but she was unaware of any clashes with police. Phones at government and police offices in Chabcha were not answered on Tuesday.
Many Tibetans in China accuse the government of religious repression and eroding their culture, as the country's majority Han ethnic group increasingly moves into historically Tibetan areas.
China rejects the allegation, saying Tibetans enjoy religious freedom. Beijing points to huge ongoing investment it says has brought modernisation and better living standards to Tibet.