Yemeni police shot dead a protester and wounded four in the main southern city of Aden on Monday, witnesses and medics told AFP.
Ali Al-Khalaqi died of his wounds at a hospital in Aden. One of the four others receiving treatment is seriously wounded, medics told AFP.
Khalaqi is the 12th protester to die in Aden since February 16, according to an AFP tally. Dozens have been wounded.
Thousands of Yemenis, including students and MPs, joined a protest near the university campus in the capital Sanaa on Monday calling on veteran President Ali Abdullah Saleh to quit, an AFP reporter said.
Security forces surrounded the protesters as they gathered in a nearby square carrying banners saying: "People want change," "People want to overthrow the regime" and "Leave".
Students, who have been protesting daily over the past week, were joined on Sunday by opposition MPs, who vowed in a statement to take to the streets.