CHICAGO (CBS) — Chicago Public Schools Chief Executive Officer Pedro Martinez said Wednesday evening that there is “no choice” but to cancel classes again on Thursday.

This follows a vote by the Chicago Teachers Union to go to virtual learning amid a COVID-19 surge – which prompted Martinez also to cancel classes Wednesday and which he and Mayor Lori Lightfoot are also characterizing as an illegal walkout.

As CBS 2 Political Investigator Dana Kozlov reported, students and parents at home are waiting for word on what Thursday will bring.

Union leaders said they were set to meet with the district at 1:30 p.m. Wednesday, potentially to hammer out some sort of agreement. But there was no update late Wednesday on how the talks went, or even if they were still happening as of 5 p.m.

Also, CPS Chief Executive Officer Pedro Martinez met with principals Wednesday afternoon to discuss what may happen next.

But as of late Wednesday afternoon, there was no indication that students would be back in Chicago schools anytime soon.

Hundreds of Chicago Public Schools teachers formed a caravan with their cars and honked their horns in Union Park after a day out of the classroom. The signs on their windshields said, “Don’t lock us out, let us teach.”

The caravan later made its way to City Hall.

A mere three days post-winter break, and all Chicago Public Schools are once again without students in classrooms. The lights went on in CPS schools on Wednesday, but it didn’t much matter – once CPS teachers voted to work remotely only, the head of the district did exactly what he said he’d do. He canceled all classes.

“Right now, going into schools puts us at risk,” said Chicago Teachers Union President Jesse Sharkey.

This is the first day of what the head of schools is calling a walkout, while the Chicago Teachers Union said its members were prepared to work remotely – only.

“This situation is not one we relish,” Sharkey said. “We’d rather be in our classes teaching. We’d like to have in-person school open.”

Sharkey said 73 percent of the 20,000 teachers who cast electronic ballots Tuesday voted to go remote due to spiking COVID-19 cases. In a post-vote letter, Sharkey told members they will return in person once the COVID surge “substantially subsides,” or the union reaches an agreement with the district that includes a student testing plan.

“Run a test-to-return program the way they have in other cities, and then once you get people back in, then have an effective screening test,” Sharkey said.

Otherwise, the union said, teachers will be out until Jan. 18, But Mayor Lori Lightfoot said the union does not get to make that call.

“We asked CTU leadership – take a moment, review the plan, come back to us with a response at the bargaining table, delay the vote – do not do an illegal work stoppage,” Mayor Lori Lightfoot said Tuesday night. “And to that, the answer was, ‘No, sorry, we’re moving ahead.’”

Kozlov asked labor lawyer Keri-Lyn Krafthefer how she saw the situation from a labor law perspective.

“Well, it really comes down to who has the ability to determine how and where services are to be provided, and that’s an inherent managerial right,” Krafthefer said.

Some teachers on Wednesday posted pictures of themselves trying to work remotely, but finding themselves locked out of the system – something that CEO Martinez warned would happen to teachers who did not report in person.

Teachers’ pay was cut off along with remote access.

Krafthefer said the city could go to court to get the teachers back in person.

“It would be a mandatory injunction, because it would be seeking to compel the teachers to return to work quickly,” she said.

A source told Kozlov the district is considering that option.

“If the mayor needs to drag us into court, you know, in order to try to force us to do what she wants, we’re going to go into court and point out that we’re doing what we think is necessary,” Sharkey said.

Meanwhile, 300,000 CPS students are left in limbo.

“We do want to get a negotiated agreement,” Sharkey said.

A spokeswoman for the CTU said she believes teachers would also be required to test for the virus unless they opt out – if any such testing agreement is reached.

Teachers also threatened not to return to work at schools last spring, but negotiated a safety plan to get back into schools. That agreement expired at the end of August, and the union said the school board did not feel it needed to negotiate another one.

Mayor Lightfoot said city officials have been talking with the union for months, but the bottom line is that no current safety agreement exists.

On Tuesday night, Martinez said he would have more information about what the rest of the week looks like for CPS students. We were still waiting for that plan late Wednesday.

At 6:45 p.m., a news conference is planned with Martinez, Mayor Lightfoot, and Chicago Department of Public Health Director Dr. Allison Arwady.