Gemstone producer Gemfields on Wednesday reported an attack near its ruby mine in Mozambique's northern Cabo Delgado province, but said operations were not disrupted.

An Islamic State-linked insurgency in Cabo Delgado has claimed thousands of lives since it erupted in 2017, disrupting multi-billion dollar natural gas and mining projects.

Gemfields, whose Montepuez Ruby Mining Limited (MRM) produced 83,990 carats of premium rubies in 2021 and generated $827.1 million in sales since 2014, said the attack occurred on July 13.

"The attack reportedly took place in the area of Muaja village, which is about 30 kilometers, by Road, from MRM. A large number of people are moving to Nanhupo and Namanhumbir, where the mining operations are located," Gemfields told Reuters quoted by VOA.

The attack was closer to the mine than previous incidents, the company said, adding that operations were not halted but continued with "increased vigilance."

Attacks have recently affected other mining companies in the region. In June, Australian-listed Triton Minerals TON.AX reported an attack against its graphite project in Ancuabe, while Syrah Resources SYR.AX briefly suspended logistics and personnel movement following attacks near its main transportation route.

Non-governmental organizations and Mozambican media, which monitor the insurgency, are reporting a push westward by the insurgents, who are said to have beheaded two men working in the fields outside Muaja, less than 10 kilometers from the district border with Montepuez.

The southern African countries, which along with Rwanda sent troops to Mozambique last year to help fight the insurgency, agreed last week to extend their deployment for another month.