A witness says students protesting in support of a teachers' strike along a major highway in Togo have clashed with security forces.

Togo's teachers are on strike this week to demand a salary increase after talks with the government failed to yield an agreement.

Franck Pissang, a journalist who was at the protest, said hundreds of students gathered on Wednesday near the town of Glei, about 125 miles (200 kilometers) from the capital, Lome. They snarled traffic on the main highway leading from Lome to the north. Police fired tear gas to disperse the crowd, and the students responded by throwing rocks, Pissang said.

Soldiers later arrived to provide backup, firing warning shots and chasing protesters in running battles.

It was not immediately clear how many people were injured.