Most, if not all, of these buildings are illegal.
Apparently, the Islamists are trying to take advantage of Passover vacations by Israeli officials to put "facts on the ground" - especially mosques and schools.
Salah makes it clear that his intention is to cause the Muslim community to surround the Jews in Israel. He said:
When we build these mosques, we are demonstrating the fact that Allah wants the existence of these villages. Right on these places, by Allah, will continue to be strong. The injustice of the occupation is a disgrace to Allah. These mosques will become central to uniting the people of the Negev, with no exceptions, and bring the union between the Negev residents to those of the Galilee, the Triangle and the cities of humiliation, all uniting under the protection of Allah the Great....We are here to fulfill an ancient national commitment. Say to our brothers in the Negev we are with them in one body and one heart, with our money and our blood. We are brothers in this country, and we share common concerns. We came here to build houses and mosques to prove we were here on our land, and we live here in honor of Allah.Mida magazine notes that this is an annual event, always happening around the time that Israeli inspectors are on Passover vacation.
I discussed the issue of illegal Bedouin Negev villages in this video I made last month.
For some reason, some illegal settlements don't get people too upset.