The sister of jailed blogger Raif Badawi has been arrested in Saudi Arabia, according to Amnesty International.

The human rights organization said Samar Badawi was detained earlier this week along with Nassima al-Sada, another prominent female activist.

The organization's Middle East research director described the arrests as part of a larger crackdown on human rights in Saudi Arabia.

"These brave women represented the last vestiges of the human rights community in the country, and now they too have been detained," Lynn Maalouf said in a statement.

Amnesty says Badawi has been repeatedly targeted by the Saudi government for her work as a human rights activist.

She was previously arrested in 2016 and subject to a travel ban in 2014.

"It appears that Samar Badawi and Nassima al-Sada are once again being persecuted for their previous human rights work and, if so, they should be immediately and unconditionally released," Amnesty's statement read.

Her brother Raif was arrested in Saudi Arabia in 2012 and later sentenced to 1,000 lashes and 10 years in jail for criticizing clerics.

He received 50 lashes in January 2015 during a public flogging but is not believed to have received any more corporal punishment since then.

His wife and three children live in Quebec and became Canadian citizens last month.

Foreign Affairs Minister Chrystia Freeland said on social media Thursday she was "alarmed" to hear of Samar Badawi's arrest.

"Canada stands together with the Badawi family in this difficult time, and we continue to strongly call for the release of both Raif and Samar Badawi," she wrote on Twitter.