The health ministry of the Democratic Republic of Congo said Monday two community health workers engaged in Ebola prevention have been killed in the eastern North Kivu province. The ministry said the workers had been receiving death threats for months.

Ministry officials, meanwhile, have confirmed the first case of Ebola in Goma, a city of more than 2 million people, along the Rwandan border.

Authorities said the patient is a pastor who took a bus from Butembo, one of the towns hardest hit by Ebola, to Goma. He arrived in Goma on Sunday and was quickly taken to an Ebola treatment centre.

The health ministry said in a statement: “Given that the patient was quickly identified, as well as all the passengers on the bus from Butembo, the risk of the disease spreading in the city of Goma is low.

The French news agency AFP reports the bus driver and passengers are receiving vaccinations Monday.

Ebola has killed more than 1,600 people in DR Congo.

Efforts to contain the disease have been hampered by violent attacks on health care workers and treatment centres.

Some Congolese people have also contributed to the spread of the disease by refusing to take their loved ones to treatment centres and not adhering to burial guidelines designed to reduce Ebola transmission.