About 70 percent of the cameras hooked up to the police’s closed-circuit TV (CCTV) system in Washington, D.C., were reportedly unable to record footage for several days before President Trump’s inauguration due to a ransomware attack.

The attack affected 123 of the 187 network video recorders that form the city’s CCTV system, the Washington Post Saturday. Each of these devices is used to store video footage captured by up to four cameras installed in public spaces.

The incident occurred on Jan. 12, eight days before the inauguration of U.S. President Donald Trump, and it took three days to restore the system. The city refused to pay the ransom and sent teams at each site to take the affected devices offline, replace their software and restart them, according to the newspaper.

The incident serves to show the dangers associated with the that target various types of systems and organizations. Last year similar attacks disrupted the IT systems at several hospitals across the U.S. and in November ransomware was used to encrypted data on about 900 systems at San Francisco’s Municipal Transportation Agency.

Saturday.