Turkish police said they have arrested 78 people accused of creating fear and panic by "sharing provocative posts" about last week's earthquake on social media, adding 20 of them were being held in pre-trial detention.
The death toll in Turkey and Syria from the devastating earthquake has climbed above 41,000, and millions are in need of humanitarian aid.
Turkey's General Directorate of Security said it had identified 613 people accused of making provocative posts, and legal proceedings had been initiated against 293. Of this group, the chief prosecutor had ordered the arrest of 78.
The directorate added that 46 websites were shut down for running "phishing scams" trying to steal donations for quake victims and 15 social media accounts posing as official institutions were closed.
Last October, Turkey's parliament adopted a law under which journalists and social media users could be jailed for up to three years for spreading "disinformation", raising concerns among rights groups and European countries about free speech, particularly ahead of presidential and parliamentary elections due this summer.
President Tayyip Erdogan's ruling party had said a law was needed to tackle false accusations on social media, and it would not silence opposition. The government has also blocked social media in the past.
Last week Turkey blocked access to Twitter for about 12 hours from Wednesday afternoon to early Thursday, citing the spread of disinformation, prompting an angry response from opposition politicians and people using the platform to find loved ones and share information about rescue efforts.
Turkey's Communications Director Fahrettin Altun tweeted on Monday that Turkey was experiencing "serious information pollution" and authorities would share a daily bulletin correcting false information.
Within a week of the earthquake, some 6,200 items of false information and news were reported to the government, Altun added.