SAN JUAN, Puerto Rico — The Puerto Rican Legislature gave Gov. Ricardo Rosselló a choice by saying that they're ready to start impeachment proceedings unless he resigns first.

The president of Puerto Rico’s House of Representatives, Carlos Méndez Núñez, has called for an extraordinary legislative session to officially begin an impeachment process against Rosselló Thursday afternoon.

The news came on Wednesday after three attorneys, commissioned by Méndez Núñez, unanimously determined there were five offenses, stemming from leaked scandalous chats, that constitute grounds for impeachment.

In the report that was leaked to the press, the attorneys found Rosselló committed four serious offenses and one misdemeanor, including illicitly using public resources and services for partisan purposes, as well as allowing government officials and contractors to misuse public funds and time for non-government work.

This is Adrian. He’s been to nearly every protest in the past 2 weeks. He said tonight was supposed to be a dance party but now - b/c Governor #Rossello refuses to resign - he things things will get ugly. It’s why he brought his gas mask and goggles. “This will be bad,” he said. pic.twitter.com/ZF5aG651rJ — Annie Rose Ramos (@Annie_Rose23) July 25, 2019

During a press conference, Méndez Núñez said the only thing that would stop the process is if the governor resigns.

If Rosselló steps down, then the report would be passed on to the relevant authorities, he added.

On Wednesday evening, a crowd of thousands had gathered in Old San Juan near the governor's mansion, shouting "Ricky, Renuncia!"

One of the protesters, Adrián, told NBC News that "tonight was supposed to be a dance party." But since Rosselló has consistently refused to resign, he's afraid things will get ugly.

“This will be bad,” said Adrián, who brought his gas mask and goggles as a precaution measure.

On Wednesday evening, a large number of reporters were assembled for hours at the door of the governor's mansion, waiting for what was expected to be a much earlier announcement from Rosselló or his aides about his future.

Rosselló's public affairs secretary, Anthony Maceira, addressed reporters two hours later, but only said that the governor was working on a statement that he would give at an unspecified time.

The turmoil follows the island's largest protest in recent history calling for Rosselló's ouster over scandals involving leaked private chats as well as corruption investigations and arrests.

Rosselló would be the U.S. commonwealth's first governor to be impeached.

News of Rosselló's impeachment process came a day after NBC News and Telemundo, both owned by NBC Universal, reported that the island's Justice Department had issued search warrants to confiscate the cellphones of several people who took part in the private chats.

Hundreds of thousands of Puerto Ricans have been protesting for 12 consecutive days, demanding Rosselló's ouster. Protests continued to grow on the island after Rosselló announced on Sunday that he wouldn't run for re-election and that he would step down from the leadership of the pro-statehood New Progressive Party.

On Monday, more than a half-million people paralyzed metropolitan San Juan in protest, marching across one of the main highways despite heavy rain in a "March of the People" that ended late in the night as police fired tear gas canisters.

The protests were first triggered by the leaking of 889 pages of private chats between Rosselló and some of his current and former officials, as well as close associates.

The chats opened local and federal probes, which come on top of recent arrests of former officials and government contractors on charges that include alleged fraud involving federal funding.

The leaked chats on the messaging app Telegram rocked the public for their profane, misogynistic and homophobic comments against public officials, celebrities and ordinary islanders, as well as their cynicism on topics that included the deaths following Hurricane Maria in 2017. The chats also revealed the administration's efforts to smear and bring down political opponents.

Nicole Acevedo reported from New York and Annie Rose Ramos from Puerto Rico.

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