QUITO, Ecuador (AP) — Thousands of protesters staged anti-government rallies Wednesday, seeking to intensify pressure on Ecuador's president after a week of unrest sparked by fuel price hikes.

Stone-throwing demonstrators clashed with police using tear gas to fend off crowds, including around the empty government headquarters in the capital of Quito.

Demonstrators struggled to get close to the headquarters in the colonial-era Carondelet palace, sealed off by police barricades in the narrow surrounding streets.

In one chaotic scene, protesters swarmed onto the top of a riot control vehicle that stopped in an alley. They pounded on its armored plating and reinforced windows with clubs and stones until the occupants accelerated away through clouds of smoke and tear gas.

Protesters included youths who burned tires and confronted security forces, labor union members and indigenous people who mobilized and marched, for the most part peacefully.

In a separate demonstration, thousands gathered in the port city of Guayaquil to condemn days of street violence that have shocked many Ecuadorians. Some wore white clothing and carried white flags.

Ecuador's Red Cross said it was suspending paramedic and ambulance services because of security concerns. Red Cross volunteers had been attacked in several locations in recent days and people threw stones at an ambulance in Quito on Monday, the aid group said.

The military earlier warned people against violence during Wednesday's protests, following unrest that led President Lenín Moreno to move government operations from Quito to Guayaquil.

In a statement, the military appealed to Ecuadorians to denounce anyone who uses the cover of the protest to carry out vandalism and other crimes.

The military's backing is key for Moreno, who said late Tuesday that his government is negotiating with indigenous groups. The president said the dialogue is difficult because so many indigenous groups are involved. He also said he will not resign despite widespread discontent in the South American nation of 17 million.

Moreno was returning to Quito from his temporary base in Guayaquil to monitor government handling of the protests on Wednesday, Interior Minister María Paula Romo said.

José Briones, secretary general of the president's office, said topics in an initial discussion with indigenous groups include aid for farmers, such as debt refinancing, irrigation and other technical assistance.

Still, the political crisis shows no immediate signs of abating. While labor leaders called the strike Wednesday, economic activity in much of the country has already been stalled by clashes, looting, blockades and other disruptions.

Ecuador's main oil pipeline, which runs from the Amazon region to Balao port on the Pacific ocean, has stopped operating because mainly indigenous protesters disrupted production facilities, the energy ministry said.