University of Michigan graduate student instructors began picketing in-person and remotely Tuesday, demanding the right to work remotely amid the COVID-19 pandemic as more cases of the virus were detected on campus.

Members of the UM Graduate Employees Union authorized a strike over the weekend, issued a list of demands and planned a teach-in over Zoom.

 The union, which represents 2,000 graduate student instructors and graduate student staff assistants at UM’s campuses in Ann Arbor, Dearborn and Flint, planned to strike for four days.It was not clear how many graduate students participated Tuesday, the first day of the walkout.

Abigail Finlay, center, a University of Michigan mathematics graduate student instructor, marches with fellow protestors in front of the University of Michigan's Angell Hall on State Street in Ann Arbor, Tuesday.

“I’m on strike with @geo3550 this week,” tweeted Surabhi Balachander, a doctoral student in UM’s English Department. “It’s not because I don’t want to work. I love teaching and am sad to miss it … I do not want my students and colleagues @UMich to get a chronic illness because this university decided it was most important to collect tuition.”

The strike comes as four UM students living in three UM dorms tested positive for COVID-19.

“This is why we fight,” tweeted the graduate student union, posting an article by The Detroit News. It ended the tweet with the hash tag, #StrikeForSafeCampus.

UM officials said over the weekend that the union was violating its contract and breaking the law by striking.

On Monday, UM posted a story about the strike vote on the University Record, a publication for faculty, staff and retirees. UM spokesman Rick Fitzgerald said to use the story as the university’s response to the strike.

“The strike vote over the Labor Day weekend followed weeks of discussions with university officials over a wide range of issues, many of them related to U-M’s plans for a mostly remote hybrid fall semester prompted by the COVID-19 pandemic,” according to the article.

John Olson, a University of Michigan G.S.I. (Graduate Student Instructor - economics) marches with fellow protestors in front of the University of Michigan's LSA building on State Street in Ann Arbor, Tuesday.

“With nearly 80 percent of all undergraduate credit hours being offered remotely, the university has granted the requests of all GSIs who have expressed a need or preference to work remotely.”

Testing and contract tracing plans have been shared, the article noted.

Many people were picketing on the grounds of UM’s campus with umbrellas, according to video posted on Twitter by UM’s student newspaper, The Michigan Daily.

The labor union representing more than 1,000 graduate students encouraged those who are not picketing to join remotely.

“We are CALLING Administrators to restate our demands! Join us!,” tweeted the union from its official Twitter account, and listed telephone numbers of officials. “We’ve heard that Regent (Ron) Weiser especially loves hearing from us :)”

At least one graduate student at Michigan State University stood in solidarity with the UM grad students.

“As a grad student at MSU, I’m fortunate to not be put in the same position at the U-M grad students, since MSU decided weeks ago that all undergrad classes would be remote this semester,” tweeted Caitlin Geier, a doctoral student at MSU. “That said, I’m going to be supporting GEO’s strike.”