The group should be watched "minute by minute," Hans-Peter Uhl, domestic politicy spokesman for the Christian Social Union (CSU) told the Frankfurter Allgemeine Sonntagszeitung newspaper.
“The situation has intensified and the assessment of these people has been confirmed, based on their behaviour,” he added.
On Saturday, followers of the Salafi branch of Islam handed out free copies of the Koran in many cities throughout the country. German security experts said Salafists advocate a radical, puritanical form of Islam that promotes extremism.
Uhl noted a hate video was released last week directed against two journalists who were critical of the Koran distribution.
Internet propaganda has to be “especially watched,” Uhl said. He noted while the distribution of the Koran is not a criminal act, it supports the “dangerous recruitment of Salafists” in the internet, and their goals are against Germany's constitution.
Saturday's action followed a call last fall from Abu Nagie, an Islamic leader, to distribute the books. Nagie is a “truly dangerous Islamist” a spokesperson for the German domestic intelligence agency told the newspaper.
"The distribution serves the goal of religious-motivated extremism," the spokesperson said.
Federal security forces have been keeping an eye on Nagie for years and state security officials will be watching what he does, the paper wrote.
Meanwhile the printer Ebner and Spiegel, which has the contract to print the Korans, said it is re-assessing whether to complete the agreement.
“If we can get out of it then we want out,” a spokesman for the company told the newspaper. He said he was expecting a decision on Monday.
Since last fall the company has printed 300,000 Korans for the Cologne-based Salafist group “The True Religion.” Nagie announced that he wants to eventually distribute 25 million copies of the Koran in Germany.