Kenyan fighter jets have bombed positions of militant Islamist group al-Shabab in neighbouring Somalia, a military spokesman has told the BBC.
The warplanes had targeted two camps in the Gedo region, used by al-Shabab to cross into Kenya, the spokesman added.
This is Kenya’s first response to the al-Shabab assault which left 148 people dead at Garissa University last week.
President Uhuru Kenyatta had vowed to respond to the attack “in the severest way possible”.
Kenyan army spokesman David Obonyo told the BBC that the military had responded to “threats” by launching the air strikes on Sunday night in the remote region.
Two camps had been destroyed, he said, adding: “The bombings are part of the continued process and engagement against al-Shabab, which will go on.”
The attack on Garissa University, about 150km (90 miles) from the Somali border, was the deadliest by al-Shabab in Kenya.
The al-Qaeda affiliate says it is at war with Kenya, and wants it to withdraw troops sent to Somalia in 2011 to help the weak government in Mogadishu fight the militants.
Governors and MPs from north-eastern Kenya have called for the closure of the Dadaab refugee camp, where about 500,000 people who fled conflict in Somalia are taking shelter.
They told a news conference in the capital, Nairobi, that the camp was used by al-Shabab as a training and coordination centre.
Aid agencies have rejected previous calls for the closure of Dadaab, the largest refugee camp in Africa.
An MP in Garissa, Aden Duale, said Kenya should “engage” with the international community to step up patrols along its long and porous border with Somalia.