Previously, in mid-April, 2008, Djibouti accused Eritrea of sending troops across the border and digging trenches and defensive emplacements inside Djibouti.

Tensions between these Horn of Africa neighbors have been escalating, in large part due to the fact that Djibouti is allied to Ethiopia, France, and the United States.  Ethiopia and Eritrea have fought two bloody wars, and maintain large military forces on their mutual border as they continue to view each other as foes.  Also, Eritrea has been accused of aiding Islamist forces in Somalia, where they have fought against intervening Ethiopian and American forces since late 2006.

The 13th Demi-Brigade of the French Foreign Legion, with 2,850 troops, shares a military base, called Camp Lemonier, with the Combined Joint Task Force Horn of Africa (CJTF-HOA) of the United States Central Command, since 2002.

Using their base at Camp Lemonier, American forces launched a Predator drone which flew over neighboring Yemen in 2002 which fired a Hellfire missile, killing al-Qaida operatives Abu Ali al-Harithi and Ahmed Hijazi, along with four other suspected terrorists. al-Harithi was believed to be a leader in the attack on the USS Cole in Yemeni waters in October of 2000. American forces based in Djibouti at Camp Lemonier also launched missions against Islamist forces in Somalia during the Ethiopian intervention which began in December of 2006.

Links:

http://www.eritreadaily.net/News0108/article0806141.htm

http://www.reuters.com/article/latestCrisis/idUSL12617339

http://africa.reuters.com/wire/news/usnL11187409.html

http://en.wikipedia.org/wiki/2008_Ras_Doumeira_border_crisis

http://www.historyguy.com/eritrea-djibouti_2008_war.html

Read the article at:

Ethiopia confirms firing incident on its border with Eritrea

Dec. 28, 2007

According to the Voice
of America:

"Eritrea has accused Ethiopia of
   attacking its security forces along the two countries’ disputed
   border.
   
   

In a statement posted on its Web site late
   Wednesday, the Asmara government said Ethiopian troops made a
   failed, small-scale attack late Tuesday on Eritrean forces in the
   South Tsorona area."

At this point, Ethiopia is denying launching any
type of attack. It is believed that Eritrea is waging a proxy war
against Ethiopia in Somalia; supplying weapons and other material to
the Islamist resistance fighting against the Somali government and
its Ethiopian allies.

The two Horn of Africa neighbors waged a bloody
border war from 1998-2000, in which over 70,000 died. The border
dispute that sparked that war remains unresolved. Eritrea gained its
independence from Ethiopia after a thirty-year long war from 1961 to
1991.

According to the International
Crisis Group‘s (ICG) Africa
Briefing of November 5, 2007:

"The risk that Ethiopia and Eritrea will
   resume their war in the next several weeks is very real. A
   military build-up along the common border over the past few months
   has reached alarming proportions. There will be no easy military
   solution if hostilities restart; more likely is a protracted
   conflict on Eritrean soil, progressive destabilisation of Ethiopia
   and a dramatic humanitarian crisis."

That report mentions a resumption of war "in the
next few weeks is very real." Reports from UN troops on the ground in
the Eritrea-Ethiopia border region of gunfire and combat on December,
26, 2007, is, literally "a few weeks" after the ICG report’s
warning.

Also, the December 13, 2007 edition of The
Economist, in an article on the ongoing border discussions and
disagreements, said:

"This time Mr Zenawi’s [Ethiopia's
   leader] belligerence comes as the Eritrea-Ethiopia Border
   Commission wound up business this month, with no agreed
   demarcation. In 2002 it awarded the disputed village of Badme to
   Eritrea. Ethiopia rejected the verdict, and has since used
   diplomatic verbiage to obfuscate and stall."

This statement, by a very respected publication,
along with the ICG’s prediction of warfare for mid-to-late December,
gives rise to increased fears that the reports of fighting on the
border may be part of a larger campaign to redraw the border and
bring things to a head.

Other links and news reports on the new fighting
between Eritrea and Ethiopia:

Fear
of War Increasing in Horn of
Africa–Associated Press, Dec. 26,
2007

Exchange
of gunfire on Eritrea-Ethiopia border:
UN–AFP, Dec. 27, 2007

Ethiopia
denies Eritrea’s fresh accusation on border
attack-Sudan Tribune, December 28 2007

The BBC has a very good article on the implications of the
Ethiopian intervention in Somalia, which is now at the one-year
mark.

See this article at:  Ethiopia
in Somalia: One year on

One very interesting point is that the Ethiopian government admits
that it was warned by the United States Central Commander, General
John Abizaid, that an invasion of Somalia would be a mistake. Abizaid
warned the Ethiopians that Somalia would become "Ethiopia’s
Iraq."

And, like America’s predicament in Iraq, with a possible face-down
with Iran, and other fronts in the War on Terror, Ethiopia also has
multiple fronts, with the strengthening of the long-running Ogaden
insurgency, and a potential new war with Eritrea to the north.

Analysis: Look for Eritrea to make a move to escalate either their
aid to the Somalis and Ogaden rebels, and/or to put pressure on
Ethiopia along the border. Reports from the United Nations indicate a
new border conflict is brewing.