Largely peaceful demonstrations in south Yemen have grown into a widespread movement demanding independence from the north. As the military crackdown against the movement intensifies, protests have turned violent.
As temperatures soar above 40 degrees Celsius (104 degrees Fahrenheit) in Aden, the great port city of south Yemen, homes become airless. Daily power cuts leave residents sweating through dark nights.
In a region where resentment of the government in the north has been festering for a decade, such daily indignities are enough to spark fury in the people.
Earlier this week thousands took to the streets in protest. Car tyres were burned, property vandalised and gun shots fired. Police were pelted with stones.
According to Yemeni officials this came after members of the opposition group known as the Southern Movement, some of whose factions call for independence from northern Yemen, ambushed a military patrol and wounded three soldiers.
The attack followed shortly on from the twice attempted assassination of an army brigade commander by members of the Southern Movement the week earlier.
In South Yemen scenes like these repeat themselves at increasingly shorter intervals.
Besieged by conflicts
In the unruly tribal strongholds of east Yemen Saleh's troops face an al Qaeda branch well integrated into the local community and whose failed attempt to bring down a US airliner last Christmas Day showed they are a menace not just to Yemen, but to international security as well.
However, to the government in Sanaa, no conflict is more serious than the growing power of the Southern Movement, whose call for independence from the north threatens the territorial integrity of the state.
The key grievance levelled by the Southern Movement against President Saleh is economic: southerners complain bitterly that despite their small numbers, just 3.5 million compared to 20 million living in the north, and despite the south being home to the majority of Yemen's oil and gas fields (which account for 75 percent of the government's revenue) the south has not witnessed anything like the economic growth and development of the north, limited though that is.
The Movement accuses the president of favoritism of northerners, working through tribal patronage networks from which southerners are largely excluded, of arbitrary land confiscation and political disenfranchisement.
The grievances date back to the unification between North and South Yemen in 1990, which was viewed by many southern leaders as failed. They were politically outnumbered by their northern colleagues, the two armies were never integrated and assassinations of southern leaders created a deep mistrust of the north. After elections in 1993, leaders of former South Yemen called for a new federal constitutional system which would decentralize power.
Instead, a year later a brief but bloody civil war erupted with northern troops occupying the south. In the wake of the victory of north over south, President Saleh amended the constitution, removing institutions of joint north-south rule and granting himself power to rule by decree.
Former Brigadier Nasser al-Qawi from the Aviation Brigade of al-Anad Air Base was one of those officers and is today one of the Movement's leaders.
"The authorities' refusal to address the issues of the South, the looting of its resources for the benefit of the ruling family and the corruption have led [the South] to demand secession from the North," said al-Qawi in an interview.
He insisted that Southern Movement demonstrations had always been peaceful, but blamed Sanaa for a violent response. "It seems the authorities want to drag us towards violence to find a justification to suppress the movement."
"The language of violence and repression used against the people of the South reflects the failure and inability of the government to provide solutions. [...] For southerners the dream faded away and turned into a nightmare. People feel the South is under occupation by the North."
Read more about the volatile situation in Yemen