(CNN) -- Egypt's military launched airstrikes in the country's Sinai peninsula, killing 13 people who the military called "extremists" loyal to the Islamist group Muslim Brotherhood, state media reported.
The Thursday night strikes hit four homes in the northern Sinai, state media reported Friday, citing military spokesman Col. Ahmed Mohammed Ali.
Details about what led to the attacks weren't immediately available. The strikes follow at least two recent deadly incidents on the peninsula.
On January 25, an Egyptian military helicopter crashed in the Sinai, killing five crew members.
The military, which said the crew was targeting militants, did not comment on what caused the crash. The organization Ansar Bayt al-Maqdis, which the United States has designated a terrorist group, claimed responsibility on several al Qaeda-linked websites.
The next day, unknown armed men attacked a bus carrying Egyptian soldiers, killing three troops and wounding 11 others, the state-run Middle East News Agency reported, citing a military official.
Egypt's interim military-backed government has blamed the Muslim Brotherhood for many bomb attacks and shootings that have taken place in recent months.
There was no immediate comment about Thursday's airstrikes from the Muslim Brotherhood, which has publicly denounced violence and called for a peaceful revolution against the government.
The government banned activies by the Muslim Brotherhood months after the military's July coup that toppled then-President Mohamed Morsy, a former Muslim Brotherhood leader.
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