The Michael Jackson memorial service is to be broadcast online, raising fears that a huge surge in traffic could cause another web meltdown.

Due to be shown later this evening UK time, the service will be shown in high definition on numerous sites, and could lead to a recurrence of the internet overload that took place when news of the singer's death broke on 25 June.

Tickets to the live event were massively over-subscribed. Around 500 million people attempted to visit the Michael Jackson Funeral site in the first hour and a half, while 1.6 million had pre-registered for a chance to receive one of 8,750 pairs.

A statement released by representatives of the Jackson family said that more resources had been added to the site to cope with demand, but it was unavailable for a time and many people were left without tickets, and are likely to watch it online.

Bloggers such as Ben Parr of Mashable have suggested that the memorial for Michael Jackson could be a "huge test for the entire infrastructure of the web" .

"This event will almost certainly shatter records for the biggest single live stream ever, and could be one of the biggest worldwide media events in history. Will the web be able to handle it?" he said in a blog post.

As news of Jackson's death started to spread last month, the internet appeared to be under severe strain. Google said that the sheer volume of search queries had looked like a denial-of-service attack, and many visitors to its News pages were greeted with the following message: "We're sorry, but your query looks similar to automated requests from a computer virus or spyware application. To protect our users, we can't process your request right now."

Twitter users were able to access only a limited number of services as the firm scaled back to cope with the traffic. The number of tweets rose to 5,000 per minute at its peak.

Over at Yahoo, meanwhile, Jackson's death led to a number of new internal records, including the most visitors to its News pages ever at 16.4 million.

"Michael Jackson's death was clearly a seminal event. And, unlike in the 1970s, we all have a remarkable tool that brings the world together - informed and connected - over those 'I remember when' moments," wrote Nicki Dugan , blog editor for Yahoo, on the Yodel Anecdotal blog.

The memorial service will take place at the Staples Center in Los Angeles at 10am Pacific Standard Time (6pm British Summer Time). Many of the major media houses are planning to show the event in full. Sky and Five will be broadcasting the event live in the UK, while Fox, CNN, ABC and CBS are planning live streams in the US. Web video serving sites including Hulu, MySpace and Facebook are also planning programmes.