JAKARTA (Reuters) - Indonesian police said on Tuesday they had evidence that a group of people accused of plotting to hijack a protest rally to lead an uprising against the government had received money transfers from an unidentified source.

Police arrested eight people on Friday for suspected treason in pre-dawn raids ahead of the rally that day by protesters opposed to the Christian governor of the capital, Jakarta.

“There is evidence of transfers,” national police spokesman Martinus Sitompul said, when asked if the group had been funded by others.

He declined to elaborate on where the funds had come from.

More than 150,000 people, led by hardline Islamists, took to the streets last week to call for the arrest of Jakarta’s governor, Basuki Tjahaja Purnama, who they say insulted the Koran.

Purnama faces trial on a charge of blasphemy that is expected to begin next week, a court official said.

The charge was filed in response to comments he made about his opponents’ use of the Koran during political campaigning. He denies wrongdoing and apologized for the remarks.

Hours before last Friday’s rally got underway, police rounded up 11 people, including the sister of former president Megawati Sukarnoputri, a former general, and a musician-turned politician.

Eight of the 11 are accused of treason and three of spreading hate speech online.

Three are in police custody.

The arrests followed weeks of simmering political and religious tension, during which President Joko Widodo repeatedly called for calm and met top military and political figures.

Widodo said “political actors” had fanned violence at an earlier protest, on Nov. 4, and the country’s police chief had warned that “certain groups” might try to occupy parliament during last Friday’s rally.