Gaza – Ma'an – Battles continued between Jund Ansr Allah and de facto Hamas police in the Gaza border city of Rafah on Friday as police tried to retake a mosque the ultra-radical group had locked down and declared an "Islamic emirate" earlier in the day.

Fifteen Palestinians were confirmed dead following the operation by Hamas' militant wing, the Al-Qassam Brigades, according to local medical sources quoted by Ma'an's Gaza City correspondent early on Saturday morning.

At least one of those killed was a high-ranking member of the Hamas wing, a Palestinian security source said. Other reports claimed a young girl was killed during the battle, which Ma'an could not immediately confirm.

Medics added that about 120 Palestinians, including civilians, were injured, many critically.

Meanwhile, de facto security forces detonated explosives at a house that belonged to the leader of the group on Friday night, according to witnesses. There were no immediate reports of casualties in that report.

But sources said the home belonged to Sheikh Abdel-Latif Abu Moussa, leader of Jund Ansar Allah ("Warriors of God"), a radical armed group thought to be ideologically aligned with Al-Qaeda, although not officially.

The Gaza-based de facto Interior Ministry issued a statement late Friday night, calling Jund Ansar Allah "mentally ill." It said officials had seized weapons from the group and would prosecute its members.

Clashes were first reported between the organization and de facto security services soon after supporters of Jund Ansar Allah barricaded themselves inside a mosque, a move seen as a display of defiance toward the comparatively nationalistic Hamas movement, which has controlled the Strip since 2007.

Earlier on Friday, hundreds of the group's supporters rallied in Rafah, declaring Gaza an "Islamic emirate."

Jund Ansar Allah leader Sheikh Abdel-Latif Abu Moussa announced the start of theocratic rule across Palestine, beginning in Rafah. Abu Moussa vowed that his organization would soon begin implementing Islamic law, a proposal counter to Hamas' efforts, with recent exceptions, to maintain the secular Palestinian legal code.

"We announce the birth of the Islamic emirate," declared another Jund Ansar Allah official, using a term popular with Al-Qaeda that describes clerical rule throughout what the organization views as Islamic land. The same speaker was photographed bearded and dressed in a red robe, surrounded by four masked men armed with assault rifles. One was pictured wearing what appeared to be an explosive belt.

The last major event involving the group occurred in July, when members barricaded inside a building in Khan Younis ultimately surrendered to de facto police. A month earlier, the group was implicated in a failed operation aimed at attacking Israel on horseback.

Among the organization's complaints against Hamas include its refusal to institute Islamic law on Palestinians in Gaza, as well as its ceasefire with Israel, which was declared unilaterally in mid-January.