hospitalised after they were found wounded and left on a street.
The families posted pictures on social media they said were of their sons showing parts of their bodies bruised and swollen from beatings.
On Sunday, the Huthis announced a ban on all demonstrations against them unless they are authorised by the interior ministry, which itself is now under their control.
The militiamen have been accused of attacking and detaining protesters as well as reporters covering demonstrations against their seizure of power.
Diplomatically, more countries shut their embassies, with Spain and the United Arab Emirates becoming the latest to announce on Saturday they had suspended operations at their missions in Sanaa.
The UAE foreign ministry said it has also evacuated all staff, following a similar move by GCC leader Saudi Arabia.
“This decision comes in light of the increasingly deteriorating political and security situation” and the “unfortunate events with the Huthis undermining legitimate authority in the country,” the UAE said in a statement carried by the official WAM news agency.
The United States, France, Germany, Italy, Britain and the Netherlands have also closed their embassies and withdrawn staff because of security fears.
And Spain said it was temporarily suspending embassy activity in Yemen “in light of the current situation of insecurity and instability in Sanaa”.
The embassy had advised all Spanish citizens to “temporarily” leave Yemen, the foreign ministry said.
And the Turkish foreign ministry “strongly” advised Turks in Yemen to leave.
The Huthis had said Western powers had no reason to shut their embassies, insisting that security was solid in the capital.
Tehran had also criticised the “hasty action” of closing the embassies, insisting the Huthis were fighting “corruption and terrorism”.
Following consultations in New York on Thursday, Britain said it would work with Jordan on a resolution to outline the Security Council’s stance on Yemen.