A three-day operation left more than 100 members of the terror group dead and destroyed 13 vehicles, Ethiopian authorities said.
Authorities in the Ethiopian region of Somali said they had "destroyed" Al Shabab militants, in a rare attack from neighbouring Somalia.
Somali's state communication bureau in a statement on Saturday said an armed Al Shabab group that crossed into the southeastern region on Tuesday "was surrounded in a sub-locality called Hulhul and completely destroyed".
A three-day operation left more than 100 members of the terror group dead and destroyed 13 vehicles, it added.
The authorities said the armed group was seeking to pass through El-Kere district in the Somali region, more than 100 kilometres (62 miles) from the Somalia-Ethiopian border.
On Thursday, officials and residents of Bakool region, on the border with neighbouring Somalia, reported Al Shabab attacks the previous day against bases hosting a special Ethiopian police unit which helps protect the frontier.
READ MORE: Al Shabab attacks African Union base in Somalia
'Heaviest fighting ever'
Mohamed Malim, a local official in Somalia's Hudur district, told AFP news agency on Thursday that "this was the heaviest fighting ever" around the towns of Ato and Yeed in the country's west.
"It continued about six hours before the militants had been repelled, there are dead and wounded combatants from both sides, but we don't have the details so far," he said.
Al Shabab, the group linked to Al Qaeda, has led an insurrection against Somalia's federal government for 15 years.
An African Union force with soldiers from five countries including neighbours Ethiopia and Kenya has supported the government in its fight against the militants.
The movement has been ousted from Somalia's main urban areas, including the capital Mogadishu in 2011, but remains entrenched in vast swathes of the countryside.
Attacks beyond Somalia's borders are rare and have mostly targeted Kenya, notably a bloody assault on Nairobi's Westgate shopping centre in 2013 which left 67 people dead.
An attack on Garissa University in 2015 killed 148 people and another incident at a Nairobi hotel complex in 2019 left 21 dead.
READ MORE: Suspected Al Shabab attack targets Kenya's Lamu region