Ethiopian troops have carried out more attacks on what they say are rebel bases inside neighbouring Eritrea, a government official said.
The official said the attacks on Saturday, a day after Eritrea called for UN action over a similar incursion earlier in the week, took place in Badme in the north of the Red Sea state.
"We've carried out further attacks on targets inside Eritrea. This time it's in the north section around Badme," the official told the Reuters news agency.
"We were once again successful. This strike was part of our plan to take proportional measures that included the [earlier] attacks in Eritrea's southeast."
The attacks are the first on Eritrean soil that Ethiopia has admitted to since the end of a 1998-2000 war that killed 70,000 people and left a border dispute unresolved. Eritrea says there have been others.
He did not specify who had been targeted in the latest attack.
On Thursday Ethiopia said it had raided three military bases inside Eritrea that it said were being using to train an Ethiopian rebel group.
Ethiopia blames the rebels for killing five foreign tourists and kidnapping two others in its remote Afar region in January.
The Eritrean government said on Friday the attacks on its military outposts were carried out with the help of the US and meant to divert attention from a decade-old border dispute between the two countries.
"The objective of the attack ... is to divert attention from the central issue of the regime's flagrant violation of international law and illegal occupation of sovereign Eritrean territories," a statement from Eritrea's foreign ministry said.
"Eritrea ... will not be entrapped by such deceitful ploys that are aimed at derailing and eclipsing the underlying fundamental issues."
Ethiopia's 'internal crisis'
Eritrea's information minister has said his country will not be sucked into renewed hostilities.
"It is those who do not know the price of war who are hungry to go to war," Ali Abdu told the AFP news agency.
"We fought enough for 30 years, and we will never be dragged into war through such hostile provocations as this."
He continued: "We do not support such groups, as these are the products of Ethiopia's own internal crisis and the result of a policy of exclusion and marginalisation."
"It is those who do not know the price of war who are hungry to go to war. We fought enough for 30 years, and we will never be dragged into war through such hostile provocations as this."
- Eritrea's information minister Ali Abdu
A vicious row over the position of Eritrea and Ethiopia's shared border remains unresolved since the end of the 1998-2000 war.
The Hague-based Eritrea-Ethiopia Boundary Commission ruled in 2002 that the border village of Badme belonged to Eritrea.
But the village remains in Ethiopia and Eritrea blames the international community, and the United Nations in particular, for not forcing Ethiopia to accept the border.
Analysts say Eritrea has launched a proxy war in lawless Somalia to weaken Ethiopia as it cannot match it militarily.
President Isaias Afewerki's government has been slapped with sanctions for links with Somalia's al-Shabab rebels.
"I suspect there is little fallout to expect from the raid, unless Eritrea chooses to unleash one of its proxies, perhaps in Somalia," said J Peter Pham, director of the Michael S Ansari Africa Centre at the Atlantic Council, a Washington-based think tank.
"Of course, if that happens, it would give the lie to Asmara's hitherto denials of linkages with groups like al-Shabab."
Concerned that tensions between the two counties could escalate, the US and France urged Ethiopia and Eritrea to show restraint and to find a negotiated solution to their differences.
"We have heard the government's reports that its forces struck military posts inside Eritrea today," Victoria Nuland, the state department spokeswoman, told reporters on Thursday.
"We are obviously calling on both sides to exercise restraint and to avoid any further military action."
Bernard Valero, the French foreign ministry spokesman, said in a statement: "France urges both states to avoid military escalation and, more broadly, to avoid raising tension. France believes the only way of resolving the dispute between the two countries is through dialogue and negotiation."
Valero said the incursion had targeted camps "which Addis Abeba accuses Asmara of using to train rebel groups operating on Ethiopian territory".
Eritrea has dismissed these claims saying that it will not retaliate against its neighbour. It termed the allegations that it harbours armed groups against Addis Ababa as a "baseless and bogus lie".