Fighting for the symbolic city of Sirte

Anti-Gaddafi fighters drive their pickup with a heavy machine gun, around 65km (40 miles) east of Sirte
Image caption The NTC's fighters may be former lawyers and truck drivers but their ability to wage war is improving fast

Sirte is one of the last remaining pro-Gaddafi bastions, under siege by an increasingly well-organised and disciplined force, but still being fiercely defended.

Latest reports from the west of Sirte suggest the city could soon fall but, after spending almost a week near the frontline on the east of the city, it seems the siege could go on still longer.

It is difficult to know how exactly to refer to the one-time rebels who emerged from among the people, but are now the armed wing of the in National Transitional Council (NTC), recognised by many nations as the new government of Libya.

Whether they are called "former rebels" or "pro-NTC fighters" they are still the same lawyers, engineers, truck drivers and shopkeepers who put their day jobs on hold to join the revolution.

But, from what we gathered crossing through their checkpoints and meeting their commanders on the long and tediously straight coastal road west from Benghazi towards Sirte, it appears they have learned a great deal.

Perhaps it is from the foreign special forces, who despite assurances of the politicians, are on the ground "mentoring" maybe even leading by example, or helping Nato aircraft and Libyan gunners hit their targets.

No doubt the knowledge brought by defections from Col Gaddafi's army has helped give them a keener sense of strategy and tactics, and of course they have learned by their mistakes.

Symbolic city

It is becoming a more advanced war, and one that appears to be some way from being over as Sirte gradually becomes more effectively surrounded and casualties become an important consideration for both the advancing forces and those trapped behind the walls of Col Gaddafi's birthplace.

Sirte a hugely symbolic city to take and, amid much speculation, some here believe it is a place the country's one-time ruler may have returned to for one final stand.

Image caption House by house, fighters check for weapons in a village near Sirte

It offers an escape route to the sea, or south into the wide open space of the Sahara desert.

The NTC have made optimistic statements about an offensive launched from the west and the south, as forces from Misrata moved to take the city.

Accurate information is hard to come by in a place devoid of cell-phone coverage, where radios are reserved for artillery coordinates and satellite phones are rare and coveted prizes.

We can only accurately report what we see and attribute what we hear to the military personnel and a new, temporary administration increasingly aware of the value of propaganda.

A colonel told me the pro-NTC troops west of Sirte had reached the final fuel station 3km (2 miles) from the city walls, but had to retreat given the heavy incoming fire.

There are no natural obstacles to an assault from that direction, but it is keenly defended by well-armed professional soldiers and, with talk of the surrounding desert being mined, it appears any breakthrough here could be costly.

In the south and the east, the distances are vast - Sirte's eastern gate is 40km from the city centre proper and there are natural defences well before you reach that, such as a wide wadi and unusually hilly stretch of desert, which gives the pro-Gaddafi forces a strong defensive line.

But the NTC military effort here in the east is most well-supplied and concentrated, and the lines are slowly inching forward.

The fighting, which continues every day, is split into two fronts - the long-distance exchange of fire with rockets and artillery shells, and the direct clashes at the very frontline.

Here, pick-up trucks with machine guns welded to them tear through the desert pushing forward and winning territory kilometre by kilometre.

'Keeping momentum'

The risks there are highest, and from the safety of the field hospital at one of the rear gun lines, it is possible to watch the Mad Max-style "technicals" go back and forth, sometimes with ambulances bringing the dead and injured.

The guns are Russian, captured from Col Gaddafi's army, and are effective over 30km.

The co-ordinates arrive from the ground or from a spotter plane above, and a mechanical engineer who studied English in Britain, translates them into angles and compass points from his logarithm charts before directing a barrage of fire.

"The points we are firing on are moving forward every day. We have plenty of rounds," he says confidently, as the radio buzzes once again.

Further forward, at the tank line, they are more used to incoming rockets, but over such distances and without the assistance of Nato satellites they are confident the pro-Gaddafi guns are firing into the dark.

The pressure is no doubt on those guns, and the commanders behind them, but it is also on those people trapped inside Sirte without supplies of food and water.

So it is a trade-off - between not moving too quickly at the cost of many lives, and wanting to keep momentum, to free civilians from the siege and to still have the support of Nato from the air - the mandate will soon run out.

The pro-Gaddafi forces are still holding the city, but how long they last may perhaps be related to what, or who, it is they are fighting for, and how well prepared they were for a siege or a fight to the death.

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