CAIRO (Reuters) - Egyptian activists and journalists have been targeted by phishing attacks coinciding with political events in an intensifying crackdown on dissent since the start of the year, Amnesty International said on Wednesday.

The rights group said it had recorded attacks against hundreds of individuals, which it said appear to be part of a coordinated campaign to spy on, harass and intimidate their targets.

They included attacks on media outlets in early February as they were reporting on proposed constitutional amendments that would allow President Abdel Fattah al-Sisi to stay in power beyond the end of his current term in 2022, Amnesty said.

“There are strong indications that the Egyptian authorities are behind these attacks,” Ramy Raoof, of Amnesty’s technology branch, said in a statement.

“These digital attacks appear to be part of a sustained campaign to intimidate and silence critics of the Egyptian government.”

Officials at Egypt’s State Information Service (SIS), the main state body that deals with the media, could not immediately be reached for comment.

Amnesty said the attacks were carried out using third-party applications to trick targets into giving access to private email accounts.

It said it had recorded a string of attacks against non-governmental organizations and media outlets in the run-up to the eighth anniversary of the 2011 uprising on Jan. 25. Authorities arrested dozens of suspects they said were planning to hold protests or commit violence on the anniversary of the uprising.

Another burst of attacks came around the time of French President Emmanuel Macron’s visit to Cairo at the end of January, peaking when he met human rights defenders on Jan. 29, Amnesty said.

It said some targets had received messages from Google warning that “government-backed attackers may be trying to steal your password”. One Reuters journalist received the same message.

Sisi has overseen a sweeping crackdown on dissent since ousting Muslim Brotherhood President Mohamed Mursi in 2013 and being elected president the following year. Thousands of Islamists and liberal opposition figures have been jailed, had their assets frozen or been subjected to travel bans.

Sisi and his supporters argue that the measures are needed to keep Egypt stable after the political and economic turmoil that followed the 2011 uprising.