Protest leaders in Haiti called the people to the streets Monday for a sixth week of demonstrations demanding the resignation of President Jovenel Moïse. Tens of thousands marched to affluent neighborhoods over the weekend, spilling oil and burning tires while riot police blocked roads.

Near-daily protests in Port-au-Prince, other cities and the countryside have shut down transportation links, shuttered businesses and closed schools, paralyzing the Caribbean nation of 11 million. At least 18 people have died in clashes with police and other violence.

Moïse, who won a controversial election in 2017 and has survived several waves of protests, appeared in public most recently last month — via a prerecorded speech broadcast on television. He’s supposed to serve three more years.

Haitians have long been fed up with poverty, scarcity and corruption. The country is perennially the poorest in the Western Hemisphere; more than half the population lives on less than $2.40 a month.

What triggered the latest demonstrations?

A deepening fuel shortage in mid-September, on top of spiraling inflation, a lack of safe drinking water, environmental degradation and food scarcity caused Haitians to block roads and highways, set fires, attack property and loot businesses. The riots led to massive marches against the government.

But it’s not just the economic crisis. In large part, it’s the sense of crippling corruption at the highest levels that has gone unpunished.

An anti-corruption movement, the “Petrochallengers,” pressured Moïse last year to agree to a formal investigation. Senate auditors reported in May that successive governments had misappropriated billions of dollars from Venezuela’s PetroCaribe oil program — a deferred payment plan that was supposed to help improve public services in the country but never did. The auditors’ report implicated Moïse directly.

People are also enraged that the island has received millions of dollars in aid since an earthquake in 2010, but public services and infrastructure remain just as precarious.

“There’s not just a political fight going on today, but the manifestation of a systemic crisis,” said Jake Johnston, an international research associate covering Haiti for the Center for Economic and Policy Research. “Haiti is facing a broad rejection of a political and economic system that in 30 years has failed to deliver results for the majority of the population. There’s a general distrust of politicians and elections. And the promises of economic development after the earthquake have clearly not been met.”

Who’s protesting?

Thousands of Haitians from all walks of life — the young, union workers, university professors, artists, business associations. Analysts say that makes these demonstrations unique: Not only are they the longest-lasting protests Moïse has faced, but the middle class and the intellectual elite are participating. The political opposition is taking part, but no single force is driving the movement.

“We are in misery and we are starving,” protester Claude Jean told Reuters on Friday. “We cannot stand it anymore.”

What are the allegations against Moïse?

Before Moïse became president, he was head of at least one company that government auditors say received money from PetroCaribe for phony infrastructure projects.

Through PetroCaribe, Venezuela provided oil to Caribbean nations with payments deferred for 25 years at low interest rates. Haiti received more than $2 billion that it still owes. According to Senate auditors, it was stolen.

Moïse has denied wrongdoing.

How has his government responded?

Moïse hasn’t appeared in public since the prerecorded speech, broadcast on television at 2 a.m., in which he called for dialogue.

As protests have grown in size and in some cases violence, police have responded with tear gas and rubber bullets. The clashes have left at least 18 dead and 189 injured, according to the National Human Rights Defense Network.

Haiti has suffered a long history of political turmoil. The country has had 14 presidents since its first democratic election in 1990. Two rose to power through coups. Only three have completed five-year terms.

What do others say?

The United Nations has called on protesters and authorities to “refrain from violence.” The U.N. Mission for Justice Support in Haiti said it is “deeply concerned” and would support “peaceful solutions.”

One factor keeping Moïse in power is support from the United States. U.S. officials have been limited in their public comments about the protests. Ambassador Michele Sison told the Associated Press last week that “we’re urging the various stakeholders to enter into a dialogue in good faith.”

What will happen now?

Moïse announced the creation of a “dialogue committee” last week to find a solution to the crisis. But the opposition, which in June published a document laying a path for a transition, categorically rejected such talks.

A coalition of 107 civil society organizations released an eight-page document on Friday supporting a transition. But analysts predicted that Moïse would attempt to wait out the demonstrations to remain in power.

Anthony Maingot, a professor emeritus of sociology and anthropology at Florida International University, described the situation as dire — and the options as limited.

“Even if they change the president, it will continue to collapse,” said Maingot, a former president of the Caribbean Studies Association. “Corruption is rampant, and the country cannot sustain its dense population with its poor land.”