Ten years ago today I was sitting at my IT support desk at an ad agency in central London – covering the early shift and waiting for the first calls of the morning to come in from tired, agitated users.

But on that day, the phones remained eerily silent and as the minutes ticked by none of my fellow techies had yet turned up for work at the office.

Eventually, some colleagues began to drift through the door, only to tell me that their journey in on the tube had been horrendous.

It wasn't clear why, however, but it was suggested that a number of London Underground lines had been hit by some sort of an electrical fire or power surge.

And still the IT helpdesk phones were surprisingly quiet on that Thursday morning.

Before long, we decided to search online for news of the apparent tube station blaze.

Details were sketchy and slow to be reported even by the likes of the BBC. While over on London forums, such as Brixton-based urban75, information was trickling in suggesting that a much darker event or series of events had taken place.

As more fellow workers turned up at the office, having travelled in on different routes across the capital, it was becoming clear that something had gone badly wrong.

We switched on the TV to try to find out more. And it was then that the first reports of a terrorist attack on Londoners were finally, heart-wrenchingly being confirmed.

It had been a little under four years since I had stood in the same building looking up at a TV monitor mounted on the wall, watching as the second aircraft slammed into the World Trade Centre on 11 September 2001.

That was the thing about working at an ad agency – television screens were plastered everywhere and they were the go-to place for news back then. Searching for instant if not-always-accurate updates online like we do today with the likes of Twitter wasn't really an option in any mainstream sort of a way.

By midday, though, we knew that three tube trains passing through or near to Russell Square, Aldgate and Edgware Road had been attacked, and that the roof of a bus travelling along Tavistock Square had been ripped open like a sardine can.

We were all stunned to hear the word "bombs", plural not singular, being reported by news broadcasters. And nobody wanted to work that day. Instead, many of us headed to a local pub to huddle together perplexed by the enormity of the events as they continued to unfold.

London suddenly felt more claustrophobic than it ever had. Transport was crippled by the attacks and many of us were fearful of using buses that were still running to travel home.

I remember street corners in Paddington being stuffed full of commuters who seemed to be frozen on the spot not knowing what to do.

It had been difficult for all of us that morning to contact friends and family as the mobile networks were jammed.

This was the city freeze-framed, boxed-in by bogeymen.

Some of us returned briefly to the office, only to be told by management to go home. It was then that one of my colleagues told me that a PA had not arrived for work at the ad agency and her boyfriend and family had been unable to contact her all morning.

I said that maybe she had been affected by the travel chaos and was unable to phone home because all the networks were down.

Eventually, having dealt with the day's backup tapes, I left the office and began a six-mile walk home to South East London. It took me hours, and while there were buses still running, I decided not to trust public transport that day.

I returned home and sat in front of the TV screen watching the tragic news until I dozed off.

On 7 July 2005, I was simply one person among a smog of millions of Londoners who were rocked by the events of that awful day.

It was roughly a week later when my company found out that one of its own had been killed in the bomb blast at Edgware Road.

I didn't know Laura Webb, beyond speaking to her once or twice on the telephone when she needed techie support. That's the thing with working on an IT helpdesk, you eventually end up – at very least – hearing all of the voices of an organisation.

But I wanted to share my story today in memory of Laura and the 51 other Londoners who died in the 7/7 attacks. ®