Berlin (CNN) -- Two men suspected of spying on Syrian opposition groups in Germany were arrested in Berlin Tuesday, authorities said.
The federal prosecutors' office said Mahmoud El A., a 47-year-old with German and Lebanese citizenship; and Akram O., a 34-year-old Syrian, are accused of having "systematically gathered information on Syrian opposition groups in the Federal Republic of Germany for years."
Acting on arrest warrants issued January 31, some 70 federal and state police officers also searched the apartment of six other suspects, prosecutors said.
The two alleged foreign agents will be brought before a federal judge Wednesday for preliminary proceedings.
The Berlin Prosecutors' Office denied any connection between the suspects arrested Tuesday and those involved in an attack on the Syrian opposition activist and Green Party politician Ferhad Ahma in Berlin last December.
The Syrian government has been accused of seeking retribution against relatives of Syrian activists working against the Bashar al-Assad regime from abroad.
The U.S. State Department announced last year that it had received reports that Syrian mission personnel had been conducting video surveillance of people participating in peaceful demonstrations in the United States. Other Syrian activists living abroad have also declined to be named or appear on camera for fear of reprisals against their families at home.
In August, a rebel military leader living in exile in Turkey disappeared from a refugee camp and reappeared days later in Syrian government custody. Evidence also suggested that the government carried out reprisal attacks against the man's family.