A man tried to enter the US embassy in Vienna Monday with a home-made bomb, but was detained by Austrian law enforcement officers.

The 42-year-old man was carrying a backpack with two hand grenades and nails inside when he attempted to step into the building in Vienna’s ninth district. The metal detectors at the institution’s entrance went off and the suspect fled.

Security personnel alerted policemen on duty at the embassy, who chased the man and managed to detain him. Police found his backpack dropped during the pursuit and inside were two grenades along with a large amount of nails.

The suspect has Bosnian background and lives outside the capital, the police said. Specialists were evaluating the grade of effectiveness of the home-made explosive device and if the suspect could have detonated it.

According to police spokeswoman Doris Edelbacher, the bomb had enough force to cause serious damage and casualties if set off.

“In case of an explosion, the bomb would have had a massive spreading effect,” she said without offering further details.

The suspect was quickly detained by police officers, who also found a book with alleged Islamic content on him. Investigators questioned the man who reportedly spoke broken German and didn’t offer a reason for his actions, reports saying he was confused.

The area was cordoned off by policemen for several hours and a thorough investigation was launched. Explosive experts were examining the content of the backpack in order to determine its provenience and destructive potential.

Nearly two weeks ago, three persons with Muslim origins were arrested in the same country for allegedly being connected with a threat video. The video reportedly released by Islamists was warning Austria and Germany to withdraw their troops from Afghanistan.

Investigators found a list containing the names of Austrian politicians believed to be potential targets of terrorist attacks.

Last month, three persons suspected of planning a series of bomb attacks targeting the Frankfurt Airport and the US military airbase at Ramstein have been arrested by German security forces.

Two German men converted to Islam and a Turkish Muslim were detained in Oberschledorn, a small town in the western state of North Rhine-Westphalia. The three were part of a terrorist organization named the Islamic Jihad Union, which was formed in Uzbekistan.

In the suspects home, investigators found a dozen containers with 730 kilos of hydrogen peroxide inside, the same substance used to fabricate the bombs detonated two years ago in London. But the quantity found by German police could have been transformed in a larger amount of explosive substance, specialists estimating it could have had the destructive force of 550 kilos of TNT.