A body was found in the undercarriage of a Lutfhansa plane that arrived at Frankfurt airport from Tehran on Thursday, according to German police and Lufthansa.

Employees at Frankfurt airport discovered a male body on Thursday morning on a plane that had arrived from the Iranian capital during a routine maintenance check at 5:30 a.m. local time, Frankfurt police said in a statement. They added that an oxygen can with a mask was found next to the lifeless body.

A statement sent to CNN by German airline carrier Lufthansa said: “We can confirm that during the routine check of a Lufthansa Airbus A340-300 after landing in Frankfurt yesterday, a dead body was discovered in the aircraft’s landing gear bay.

“The responsible authorities are currently on site to investigate the background together with experts from the company. We ask for your understanding that we cannot provide any further information against the background of the ongoing investigation,” the statement went on to say.

According to the Lufthansa flight schedule, the direct flight on this route takes five and a half hours. Friday’s regular flight was canceled after the discovery, Lufthansa’s website showed.

The incident comes amid nationwide protests in Iran that have gripped the country for weeks, following the death of 22-year-old Mahsa Amini.

Tens of thousands of protesters took to the streets of Berlin last Saturday in a show of support for the ongoing anti-government protests in Iran.

Germany’s Foreign Minister Annalena Baerbock on Wednesday announced that Germany will adopt further restrictive measures, including to impose entry restrictions on Iranian nationals over the deteriorating human rights situation in the country.

On Thursday morning, Iran’s foreign ministry summoned Germany’s Ambassador to Tehran, Hans-Udo Muzel, accusing Berlin of interfering in the Islamic Republic’s internal affairs, the semi-official news agency Mehr News said.

Germany’s Foreign Ministry on Friday said it had summoned the Iranian ambassador in a reciprocal move on Thursday in Berlin.

“In both cases, talks focused on the package of measures presented by Foreign Minister Annalena Baerbock on Wednesday in which we are adjusting our relationship with Iran in light of the massive violence against its own people,” Andrea Sasse, Germany’s foreign ministry spokeswoman, told reporters at a regular press briefing in Berlin.

“Talks also focused on German security facilities in Iran and vice versa,” Sasse said. (CNN)

PHOTO CAPTION:•Frankfurt airport in Germany, where a body was discovered in a plane's undercarriage on Thursday.