Egypt escalated its crackdown on the Muslim Brotherhood on Thursday, Dec 26 detaining at least 16 of the group's supporters on charges of belonging to a terrorist organization the day after it was declared one by the government, Reuters reported.

The activists were held in the Nile Delta province of Sharkiya on suspicion of "promoting the ideology of the Muslim Brotherhood group, distributing its leaflets, and inciting violence against the army and police," the state news agency said.

The government declared the Muslim Brotherhood a terrorist group on Wednesday in response to a suicide attack a day earlier that killed 16 in the Nile Delta, accusing the group of carrying out the bombing. The Brotherhood condemned the attack.

Interior Ministry spokesman Hani Abdel Latif told state TV on Thursday that anyone taking part in Brotherhood protests would be jailed for five years. "The sentence could be death for those who lead this organization," he added.

Earlier in the day a bomb explosion in Cairo wounded five people, and Latif said a second similar home-made device was found nearby and dismantled.

The government did not provide evidence to back up the charge that the Brotherhood had staged the Nile Delta attack in Mansoura, north of Cairo, which was claimed by the Sinai-based radical Islamist group Ansar Bayt al-Maqdis.

Ansar Bayt al-Maqdis has taken responsibility for several other major bombings, including a failed attempt to kill the interior minister in September.

The Brotherhood's Islamist allies responded defiantly to the cabinet decision announced late on Wednesday, vowing to continue the protests it has staged against the army since the overthrow of President Mohamed Mursi.

"The putchists are a terrorist organization. The Brotherhood are peaceful patriots," they said in a statement.