Following an influx of new fingerprint sensor evidence that emerged over the weekend, a new Wall Street Journal report and a photograph of what appears to be an iPhone 5S user guide suggest the 'Touch ID sensor' beneath the Home button is very likely to make an appearance at Apple's iPhone event today.

See: Apple iPhone event live feed

WSJ's report cites people familiar with the matter who claim that there will be a fingerprint sensor built into the "more expensive of two iPhones," which suggests the iPhone 5S will get the new technology but the expected cheaper iPhone 5C will lack the sensor.

The introduction of a fingerprint sensor in the iPhone 5S could lead to interest among other smartphone makers, according to the report. Back in January, KGI Securities analyst Ming-Chi Kuo predicted that the rumoured fingerprint sensor could spell trouble for competitors, as it'll be difficult to integrate the technology into other devices that don't have a physical button to embed it beneath.

In addition to the Wall Street Journal report, a new photograph of what appears to be an iPhone 5S user guide shows a 'Home button/Touch ID sensor' label, adding further evidence to the fingerprint sensor theory.

The photograph, which was published by on Monday, shows a quick start user guide for an iPhone 5S. Annotations pointing to the iPhone 5S's features point to the sleep/wake button, ring/silent switch, volume buttons, the Lightning connector and a "Home button/Touch ID sensor."

The Home button appears to have a silver ring around it, a feature rumoured to be part of the fingerprint sensor technology. A recently discovered Apple patent suggests that the silver ring could be an integral part of the sensor's functionality, rather than an aesthetic touch.

With the fingerprint sensor rumoured hotting up, concept designer Martin Hajek has created some excellent mock-ups that show what the iPhone 5S with the fingerprint sensor could look like. Visit Martin's website for the full gallery.

Rumours of a fingerprint sensor in an upcoming iPhone sparked when Apple acquired AuthenTec last year, a company that specialises in security systems such as fingerprint sensors.

Code spotted in an iOS 7 beta in July provided key evidence to suggest that the iPhone 5S would be the first iPhone to take advantage of the technology.

Plus, the white circles on Apple's official media event invitation look a lot like the rumoured Home button with the silver ring around it, so they could be a big clue to what we can expect at the event tonight.

See: Apple decorates iPhone event venue with colourful banners

We'll be bringing you live coverage of tonight's iPhone launch event, so tune in from 6pm BST to find out what Apple is unveiling as it happens. Bookmark our live feed and join us later when the event is about to begin.

See also:

Get your Mac ready for Mac OS X Mavericks

Black iPhone 5S and blue iPhone 5C most popular choice among potential customers

Queuers camp outside Apple Store for iPhone 5S, iPhone 5C, before they're even unveiled