The perpetrators of a bombing attack on a Tel Aviv bus last month plotted to assassinate government ministers and other Israeli officials, according to new details of an investigation released Wednesday.

Israel's Shin Bet security agency and police apprehended four members of a cell affiliated with Hamas and Palestinian Islamic Jihad shortly after the Nov. 21 attack, in which 28 people sustained light to moderate injuries.

"Investigations showed that they also considered assassinating senior members of the government and mayors, as well as additional attacks against soldiers and civilians at various locales, including suicide bombings and drive-by shootings," Shin Bet said in a statement issued by the military following the lifting of a gag order.

It added that members of the squad, most of whom hail from the West Bank village of Beit Lakiya, were in the process of collecting intelligence for these attacks at the time of their arrest.

The details emerged hours after a Tel Aviv court earlier Wednesday indicted Mohammed Mafarja, an 18-year-old Palestinian suspected of planting the remote-controlled explosive device on the No. 142 bus in central Tel Aviv on the last day of "Operation Pillar of Defense," the army's offensive against rocket crews in the Gaza Strip.

Mafarja legally resided and worked in Israel, exploiting the unfettered access provided by his Israeli ID to reach Tel Aviv and execute the attack, Shin Bet said. He was charged Wednesday with aiding an enemy during war-time, multiple counts of attempted murder, conspiring to commit crimes and dozens of counts of causing grievous harm.

A trial date has yet to be set. The suspect's lawyer requested three weeks to review the charge sheet.

The Shin Bet said its interrogation of Ahmed Moussa, a senior Hamas member and the cell's leader, revealed that he had " extensively researched" the internet for information on producing explosive devices and methods of remotely detonating them using cell phones.

Outraged by Israel's assassination of Hamas military chief Ahmed Jabari and the bombing campaign against Gaza militants that ensued, Moussa accelerated his plan to strike a densely-packed city bus, assembled and delivered the bomb, instructed the bomber on where to place the device and activated it himself, the statement said.

The cell's other members were nabbed in the Israeli Arab town of Taibeh and are also facing indictments. The Shin Bet statement named them as Fuad Azai, 27, an Islamic Jihad member previously imprisoned in Israel for militant activity, and Hamas member Mohammed Damara, 25, a resident of a village north of Ramallah, who planned to recruit students from a Palestinian university in the West Bank for suicide bombings in Israel.