* Army says kills 16 militants in Sinai
* New group says carried out Cairo bombings
* Army says roadside bomb defused in Sinai
* Police say seize bombs in raid outside Cairo (Recasts with air strike in Sinai)
By Tom Perry
CAIRO, Feb 8 (Reuters) - The Egyptian army said on Saturday it had killed 16 Islamists in Sinai, and a new group said it carried out a bomb attack on police in Cairo, underscoring the widening scope of militant violence since the army removed Mohamed Mursi from power.
The army said its aircraft hit radical Islamists near Sinai's border with the Gaza Strip on Friday evening. A statement described them as belonging to the Muslim Brotherhood, which denies government accusations it has turned to violence.
The army has been trying to wrestle control of North Sinai from armed Islamists who have turned their focus from Israel to the government since Mursi, a Brotherhood member, was deposed in July following mass protests against his rule.
The state has declared the Brotherhood a terrorist group. The Brotherhood says it is committed to peaceful activism.
The army said on Saturday a roadside bomb planted to target military personnel had been defused in Sinai.
While many of the attacks on the security forces have been focused in Sinai, bombings and shootings have become increasingly regular and lethal in the Nile Valley and Delta.
A statement issued by the new militant group - Ajnad Misr, or Soldiers of Egypt - claimed responsibility for two bombings in Cairo that targeted the Egyptian police on Friday and vowed to carry out more attacks against the security forces.
Ajnad Misr emerged late last month, claiming responsibility for six attacks at the end of January, according to SITE. "(The security forces) are not safe from retaliation which is pursuing them," its statement said.
"Our attacks on them will continue all the while their crimes continue," the statement said.
The statement was posted on a Facebook page set up in its name and quoted by a website used by militant groups and by SITE Intelligence group, which monitors such sites.
Many of the attacks have been claimed by Ansar Bayt al-Maqdis, a group based in North Sinai.
The army-backed authorities have cracked down hard on Mursi's Islamist sympathisers since his removal. Hundreds of his supporters were killed during protests in the weeks after his removal and thousands more were arrested.
Several hundred members of the security forces have been killed in bombings and shootings since then.
In a raid outside Cairo, the Interior Ministry said police seized an arms cache including 10 bombs stored at an apartment by a member of the Muslim Brotherhood.
The Interior Ministry said one of the bombs seized in the raid on the apartment outside Cairo in 6th of October City, 30 km (19 miles) from the capital, weighed 25 kg (55 pounds) and was equipped with timers and remote controls. The other nine were described as primitively assembled.
A suspect had confessed to belonging to the Muslim Brotherhood and said he had received the arms from a member of the group's political party, the Interior Ministry said.
The Brotherhood, most of whose leadership is in jail, has denied such accusations in the past. (Writing by Tom Perry; Editing by Ralph Boulton)