BERLIN (AP) ― Nobel literature laureate Guenter Grass has been admitted to a hospital in Germany, days after his poem criticizing Israel triggered a storm of controversy.

German news agency dapd reported that a Hamburg hospital confirmed the 84-year-old was being treated but gave no details.

In his poem “What Must Be Said,” published April 4, Grass criticized what he called Western hypocrisy over Israel’s nuclear program and labeled the country a threat to “already fragile world peace” over its stance regarding Iran.

A few days later, Israel’s interior minister announced that Grass ― who only a few years ago admitted to serving in the Nazis’ Waffen-SS during World War II ― would be barred from Israel. The official cited an Israeli law that allows it to prevent entry to ex-Nazis.