Two young volunteer teachers were attacked with acid on the east African island of Zanzibar, local police said Thursday.
The British women were injured in Stone Town, the island's historic center, after two men on motorcycles threw acid and then fled the scene. The victims were identified as Katie Gee and Kirstie Trup, both 18, according to officials.
The attack occurred Wednesday while the two women were walking in the town alone. None of their belongings were taken, said police Cmdr. Muccadam Khamis to CNN News. Motive for the attack remains unknown.
Family members released the photo of one of the victims, taken after the attack, in hopes that more people would come forward with information regarding the attack. The streets were deserted at the time and no security cameras were available to capture the event.
"There were no CCTV cameras when the attack occurred and the streets were deserted, so it's hard to catch those involved without eyewitnesses coming forward with information," Mkadam told the New York Daily News.
The government offered assurance on Thursday, confirming that the case would be carefully investigated.
"The event is a great tragedy, and an attack of this nature against a foreign citizen, has never happened here before," the Zanzibar government said in a statement. "The government is appealing to the general public to assist in the arrest of the offenders and is offering a reward of 10 million shillings (about $6,000) to anyone providing information leading to an arrest."
So far, at least five people have been questioned in the attack; two of those people are still being held.
"We have so far questioned five people over the acid attack. Three have been released and two are still being detained for further questioning," Zanzibar Urban West regional police commander Mkadam Khamis Mkadam told Reuters. "We believe they were at the area when the attack occurred."
The women were flown in to a west London military base on Friday.