At least 120 protesters in Bahrain have been wounded in renewed clashes with police this week.
Activists calling themselves the "February 14 Youth Coalition" called for more demonstrations to mark the first anniversary of the nation's violently suppressed pro-democracy uprising.
"There were over 100 cases on Tuesday and 37 of them are bad, with head injuries and fractures," a medic who works with an international human rights group and asked not to be identified told the Associated Press. "On Monday we had 20 people (wounded) in all villages around the country."
The medic said some casualties had been hit by birdshot pellets, which Bahraini police deny using.
According to local human rights activists most of the wounded are being treated in village homes or private health clinics because the protesters fear they will be arrested if they go to government hospitals.
The Interior Ministry said on Tuesday that rioters had caused chaos and vandalism in several villages, but gave no information on how many had been wounded or detained.
Bahrain, which hosts the U.S. Fifth Fleet, is aligned with the United States and oil giant Saudi Arabia in their disputes with Iran over its nuclear program and regional influence.
Bahraini forces backed by Saudi troops crushed last year's month-long revolt. During the revolt 35 people, including security personnel, were killed. Bahrain's state of emergency was lifted in June.
Opposition leaders want Bahrain to move towards a fully-fledged parliamentary democracy where the elected house can form governments, a reform which would be a first in the Persian Gulf. It would also greatly reduce the extensive powers of the ruling al-Kalifa dynasty.
Tensions in Bahrain have simmered since the uprising, with intermittent clashes between Shiites and riot police erupting, while the opposition and government accuse one another of refusing to negotiate.
Former Shi'ite Wefaq party lawmaker Jasim Hussain told AFP that party leaders, representing the largest opposition faction, had met Royal Court Minister Sheikh Khaled bin Ahmed to discuss breaking the deadlock.
"There is fresh attention now, but the authorities have to show seriousness," he said, without giving details. "The new thing is that the government is increasingly becoming a partner and realizing that the security cannot solve the issue."
Wefaq leader Sheikh Ali Salman has called on youths this week to avoid into violent confrontation with police.