ANN ARBOR, Mich. (AP) — The University of Michigan’s new president, who also plays the cello, has scratched a highly publicized appearance with a local orchestra, the result of rising tension between the school and striking graduate student instructors.

Santa Ono was scheduled to perform Saturday with the Ann Arbor Symphony Orchestra during Brahms’ “Hungarian Dance No. 1.” The work has been dropped from the program.

Striking members of the Graduate Employees’ Organization “have been very aggressive with protests at his events,” university spokesman Rick Fitzgerald said Friday.

Ono was “being sensitive to the Ann Arbor Symphony and its audience” by withdrawing, Fitzgerald said.

Ono’s dinner with students at a restaurant was disrupted by strikers Thursday. The university’s governing board said protesters “banged on the windows” and “came dangerously close to violence.”

Two protesters were briefly detained by police as onlookers yelled, “Let them go!”

Irene Promodh said fellow union members simply wanted to talk to Ono about losing pay during the strike, which began March 29.

The union bargains on behalf of more than 2,000 graduate student instructors, though not all are on strike. Ono has been university president since October.