Company officials told Dow Jones Monday afternoon that there were just 20-30 protesters at the site with stones and scrap metal, but it could not determine when shipments could restart.

The group has been barricading the railroad since about noon local time Sunday. It is the second demonstration in less than a month.

Moatize ships between 10,000 and 12,000 metric tons of coal daily and conducts mining 24 hours a day, seven days a week.

“The situation is calm,” a Vale official told the wire service.

“We're confident in the company's position.”

Vale’s position, which is obviously a point of contention, was to relocate the brickmakers from the Moatize concession starting in 2010. It has compensated three groups of them thus far at approximately $2000 per oven.

Vale said 63 brickmakers were still awaiting payment, but the first group that was paid in 2010 is at the center of the complaint over the reimbursement’s “insignificant value”

“[The company] doesn't consider the production of bricks in Moatize to have been paralyzed or to be paralyzed by the coal-mining project,” company officials said.

“It was merely transferred from the area of the mining concession to another area in Moatize, where it continues to be done.”

The miner added that, in a latest round of government-mediated discussions between the two late last week, the workers “abandoned the principle of bringing together existing positions” and presented fresh compensation proposals.

Some in the group are requesting compensation for lost production of up to two family generations.

Vale told the outlet that the additional requests were not justified, but it was willing to continue discussions with the workers.

The first protest action in April resulted in shots being fired into the air in an attempt to disburse about 300 protestors.

“Police are shooting into the air with real bullets,” community activist Rui de Vasconcelos told local media at the time.

“They want people to disperse.”

The protests escalated during the second day after the movement’s leader, Refo Agostinho, was arrested, with the police station where Agostinho was held being picketed.

The picketers vowed not to move until Agostinho was freed, de Vasconcelos said.

"The constitution gives us the right to protest,” he said.

“Why do police react like this?"

AFP reported that three people were hurt in the protest while trying to flee police.

Earlier this year, Vale said it was planning to ship 4.5 million tonnes of coal from Moatize during 2013.