* Protests highlight local resentment against mining firms
* Mining companies say many locals lack skill to be hired
The main rail route for moving Mozambique's coal to port from mines owned by Vale and Rio Tinto, reopened on Tuesday just two days after being blocked by protests, Vale said.
The stoppage on the Sena line highlighted resentment against mining companies from locals who may live on less than $400 a year and want to see a larger share from the natural resources boom.
The line, the only railway from the coal-rich Tete province in the northwest, was blocked by brick makers whose businesses were resettled by Vale and who are now asking for compensation.
"They are now realizing that they have given up a lot of their rights," said Julio Calengo, an official at the Human Rights League in Tete.
Police said officers had dispersed the crowd and arrested three protesters. They denied reports of shots being fired.
"We do not want to fight. We are demanding our rights," protester Taibo Mahomed told Reuters. "Vale needs to attend to us better. They are making a joke out of a very serious problem."
Vale said there were no grounds for the bricklayers' demands, saying production was continuing at full-scale after being moved to another part of town.
Resettlement remains an issue for firms who have arrived in the war-scarred southern African state since 2004, hoping to secure some of its estimated 23 billion tonnes of coal reserves.
The entrance to Vale's mine was blocked last month and hundreds of locals took to the streets in early 2012, protesting against what they said was a lack of water, electricity and fertile farming land at their resettlement area.
The mining boom has brought a mixed reaction in Tete, a dry and dusty town 1,500 km (950 miles) north of Maputo.
The number of banks, hotels, markets and gas stations has swelled but the stream of foreign investment has bypassed many locals, with educated workers from the south who have chased the mining boom reaping some of the rewards.
Instead, locals, often lacking the necessary skills, are left with the burden of more expensive food, fuel and rent. Only just over a third of Vale's staff in Mozambique are from Tete.
"If I could point to one difficulty, it would be the managing of expectations," Ricardo Saad, Vale's Africa director told Reuters in March. "For people to take over a more significant portion of the jobs, they need education."
Vale said it has implemented programmes to train locals on everything from railway operation to agriculture, but often the jobs on offer are not enough: this year, over 6,000 applied for just 150 internship spots.