Ebola response workers in eastern Congo have staged protests this week to call for the government to pay salaries and allowances that they say are nearly three months overdue, as security incidents continue to hamper efforts to contain the outbreak.

Dozens of health workers gathered outside Ebola treatment centres in Bunia, Rwampara and Mongbwalu, all in Ituri province, on Sunday and Monday, calling for immediate payment of the salaries and allowances, protesters said.

In the protest in Mongbwalu on Monday, police dispersed demonstrators after they caused a disruption outside a hospital, local authorities and a protester said.

"We are facing an unjust situation that seriously jeopardises the continuation of the response effort," the health workers said in a letter addressed to President Felix Tshisekedi. He has not publicly responded.

Congo's communications ministry did not respond to a request for comment.

Ebola response efforts also continue to be disrupted by security incidents amid persistent community mistrust.

A group of young men in Niania, also in Ituri province, briefly blocked a UN World Food Programme helicopter from landing on Tuesday and threw projectiles at an Ebola treatment centre, prompting police to fire warning shots, according to local civil society leader Samuel Banapia.

In neighbouring North Kivu province, rumours on social media that health authorities planned to impose a curfew sparked protests in Butembo on Monday, Katwa health zone chief Jean Mukoko told Reuters.

An ambulance sent to evacuate a suspected Ebola case was vandalised in Beni on Saturday, a local health official said.

The outbreak has infected 3 802 people and killed 1 707 since it was declared on May 15, according to the latest government data released on Monday, and is now the second-largest on record globally.