Zanzibar: Two British women have had acid thrown in their faces on the east African island of Zanzibar, police have said.
The pair, both reportedly aged 18, were believed to be working as charity volunteers on the island.
They were flown to Dar es Salaam in mainland Tanzania for treatment, but their injuries were not said by official to be life threatening.
The Foreign Office said it was "aware of an incident" and was "providing consular assistance".
Police said two men on a moped threw the acid at the women, splashing their faces, chests and hands as they strolled through the streets of Stone Town, the old part of the island's capital Zanzibar City, which is a Unesco world heritage site.
Deputy police commissioner Mkadam Khamis told AFP news agency: "The motive for the attack on the volunteers aged 18 years, has not been established. Investigations are on until we apprehend the criminals."
The police on Zanzibar said it was the first time foreigners had been attacked in this way.
The Foreign Office's travel advice for the semi-autonomous Zanzibar is the same as that for the rest of Tanzania.
The Foreign Office says that while the majority of 75,000 British nationals have "trouble free" visits to Tanzania every year, "violent and armed crime is increasing" and "there is an underlying threat from terrorism".
It also says that "mugging, bag snatching (especially from passing cars) and robbery have increased throughout the country" and "in Zanzibar incidents have taken place in Stone Town and on popular tourist beaches".
Recent attacks in Zanzibar include an acid attack on a Muslim cleric in November, and the shooting dead of a Catholic priest in February. Another priest was shot and wounded in December.