JAKARTA, Sept 15, Reuter - More than 100 students marched through the ancient Indonesian city of Jogjakarta on Friday protesting against the army's use of bayonets to disperse demonstrators, witnesses said.

Contacted by telephone in the central Javanese city, they said students marched on government offices with banners reading "Army keep your hands off the people".

Diplomats and human rights activists said soldiers stabbed six students with bayonets as they staged a sit-down protest last week against harsh jail sentences imposed on fellow students.

They said three were still in hospital.

A military spokesman said only one student, who was now at home, had been wounded and that was self-inflicted. He gave no other details.

Students have been at the forefront of stumbling progress towards more open political discussion in Indonesia, ruled with a tight grip by President Suharto for nearly 25 years.

Suharto, a former general who came to power with the backing of the military, earlier this week told reporters that openness had already been carried out.

Last week's demonstration was sparked by the sentencing of two students -- to seven and eight years in jail -- for subversion by spreading Marxism, selling books less than 24 hours after they had been banned.

"The openness thing is talk, talk, talk. The minute there is any action, the courts are throwing people in prison and the armed forces are back out there cracking heads," one diplomat said.

In Bandung, about 300 kms (185 miles) west of Jogjakarta, students began a hunger strike in protest against the expulsion of nine colleagues for their part in a demonstration during which objects were thrown at Home Affairs Minister Rudini.