By Charles Haviland
With the civil war in Sri Lanka apparently in its final days, the government is accusing Tamil Tiger rebels of causing a humanitarian disaster with tens of thousands of civilians thought to be trapped in the tiny remaining stretch of rebel territory.
Earlier this week, at dead of night, a massive electric storm hit Sri Lanka's western coast. Lightning flashed through the skies, illuminating Colombo's gracious colonial bungalows and proud commercial skyscrapers, its temples, churches and mosques.
The national army now has the Tigers on the run.
The ocean, always rough and strewn with breakers in this city, roared as it hurled itself at the coastline.
And the thunder, again and again, seemed to rip from the skies down to the ground.
Lying sleepless because of a mere thunderstorm, I thought of how others, just over on the other side of this island, must also be sleepless, probably for weeks on end - and of the far worse sounds they must listen to.
A tiny and ever-shrinking strip of land between a lagoon and the sea is now all that remains of the territory held by the Tamil Tigers.
Packed in there and mostly brought in by the Tigers as they suffered one military setback after another, are tens of thousands of civilians.
They are living in makeshift shelters, densely packed together on the shore, without the basics of decent life, and constantly at risk of being caught in the crossfire of bitter war.
Many of those worst off, who the Red Cross evacuated by ship, have wounds from shrapnel, bullets and grenades.
Gone are the days when the Tamil Tigers held whole swathes of northern Sri Lanka, running their own police force, schools and courts - the fledgling Tamil homeland that they built up with ruthless single mindedness. They are said to have invented suicide bombing.
The national army now has the Tigers on the run. The latter are widely accused of keeping those desperate, remaining Tamil civilians as human shields to try to frustrate their own final crushing, although the Tigers deny doing this.
This week though, things suddenly moved on. Journalists were hurriedly called to air force headquarters.
Sri Lanka says more than 160,000 people have fled the fighting
Our passes were checked and we were escorted past a serene statue of the Buddha into a building which felt more like a luxury hotel than a sub-continental military nerve centre.
Several floors up, in a darkened room, a courteous, calm man, the director of air operations, guided us through some extraordinary aerial footage shot early that day by an unmanned aircraft.
It showed people, like ants on the screen, moving as quickly as they could, apparently away from the Tiger-held coastal strip and towards government-held land where there was no fighting.
We were told this was made possible after the army breached a long rebel wall.
Some shots showed people wading through the swampy lagoon.
"Clearly they were not inside there of their own free will," said our air force friend.
In other pictures, tens of thousands milled around, waiting to be processed at military checkpoints before being moved to government camps.
We also saw video transmitted live from the aircraft. It was eerie.
Doctors say many people have been treated for gunshot and blast injuries
Thousands of tarpaulin shelters on a golden beach by a turquoise sea. Little life was visible. Were people sleeping, or had they fled, or something worse?
The exodus continued from Monday into Wednesday. It then appeared to dry up, leaving many wretched people still in the shrinking rebel zone.
Journalists like me could only report it from Colombo, using whatever information we got from the government with a little from the rebels - for throughout the early part of the week, as has largely been the case for many months, we were not allowed in the north.
In the capital the atmosphere is one of growing celebration, and sometimes triumphalism.
And it does seem that huge numbers of Tamils have been able to escape from, in effect, being held hostage.
The triumphalism, though, can be discomforting. I chanced on a TV channel in the majority Sinhala language.
Three people, including a Buddhist monk, were giving recitations backed by images of soldiers.
Many Tamils have fled by sea, the Sri Lankan army says
There were constant sound effects - the noises of explosions and shooting.
Although Colombo has a large Tamil population, you would not know it from the many posters of the smiling president and the heroic army troops, decked with slogans written only in Sinhala.
It is often said that the war in Sri Lanka, and seeing it through to the end, are popular with the public.
But do the Tamil population feel fully included in that victory, given that the armed forces have virtually no Tamils?
I ask not because I assume most Tamils support the Tigers. I am sure they do not. But because there is clearly an ethnic issue that will remain unresolved even when the guerrillas are crushed.
"That law in 1956 demoting Tamil and promoting Sinhala and Buddhism as the only official language and religion was a big mistake," I was told on my first day.
"In this town, at the military checkpoints, just for speaking Tamil you are regarded as a terrorist," my friend went on.
The man talking to me was not a Tamil activist. He was a thoughtful and senior government official.
From Our Own Correspondent was broadcast on Saturday, 25 April, 2009 at 1130 GMT on BBC Radio 4. Please check the
for World Service transmission times.