GUANTÁNAMO BAY NAVAL BASE, Cuba — The number of detainees at the wartime prison here deemed to be on a hunger strike by the military spiked again on Friday, to 63. Defense lawyers contend that an overwhelming majority of the 166 prisoners have been participating in the protest.

Still, the official count of 63 was an increase from 52 on Wednesday. On April 12, the eve of a briefly violent predawn raid by guards who forced prisoners living in communal cellblocks into lockdown in individual cells, there were 43 participating.

Military officials told reporters this week that the detainees who had been living in the communal cellblocks, who previously had complied with rules, had been increasingly unruly amid the hunger strike. They had covered surveillance cameras and refused to go into their cells for daily lockdowns that enabled guards to enter the recreation yards and common space.

A Muslim cultural adviser to the military who has worked here since 2005, identified only as “Zak” for security reasons, told reporters on Thursday that the military had given the prisoners time to start complying with the rules again, but the prisoners refused.