Tesco shares plummeted following a profit warningReuters

Tesco shares have fallen to a 12-year low, but some analysts say that the embattled grocer's stock price could fall further.

According to a range of analysts, Tesco shares are being sold-off as investors worry over why fraud investigations are taking so long to come to a conclusion.

"Tesco shares are being sold off as a sentiment play as they are haemorrhaging market share and the investigations over the overstatement of profits is taking so long," David Buik, market commentator at Panmure Gordon told IBTimes UK.

"If someone were to say that Tesco shares would fall to 140.00p – I wouldn't laugh at them. Tesco's share capital has fallen from its height of £28bn (€35bn, $44bn) to £12.5bn but their assets are worth significantly more than that.

"However, their retail operation is in serious trouble and many people are speculating over why the review and investigation is taking so long to come to a conclusion. Investors worry that the overstatement of profits may not be a one off and that there are more creative accountancy transgressions over a longer period of time."

The Tesco stock price has had 55% of its value removed since the start of the year. It plummeted by over 16% in the market open on 9 December after the group confirmed that the full financial year "will not exceed £1.4bn" in profits.

So far today (9 December), at its lowest point, Tesco shares hit 157.29p.

This is well below the £1.8bn to £2.2bn range expected by markets.

Tesco had already cut its full-year profit forecast from £2.8bn to £2.4bn in August this year.

"If we look at the direction of the stock over the course of the year, it's been pretty much downwards trajectory," said Daniel Sugarman, market strategist at ETX capital to IBTimes UK.

"It definitely could get worse and anyone looking at the stock can see it falling dramatically and there could be some way to go.

"2014 is a bad year for Tesco and I don't see any positive news coming out this year for them. Management is clearly trying to calm the markets and shake things up but it's unlikely to have an effect on the stock over the next month."

In addition, Sugarman warned about investors holding onto the stock in the long term in a bid to "bag a bargain" from the shares trading at rock bottom prices.

"It's lovely to hear that some people are thinking positively but never assume a stock that has plunged 90%, won't go down by another 90%. If people are looking at the groundfloor, they maybe clutching at straws. We have no idea what is going to (to come out of the reports) in the near future."

Tesco still faces a Serious Fraud Office investigation into how the group overstated profits by at least £250m.

Tesco launched its own internal investigation, led by Big Four accountancy Deloitte and law firm Freshfields, and the results are set to be released in January next year.

Reports have also emerged that a whistleblower had notified the group about concerns over its profit declarations but was "ignored for months".

Newly installed Tesco boss Dave Lewis has overhauled the management structure of the British retailer in the wake of an accounting scandal that led to eight managers being suspended.

"While it's slogan may be 'every little helps', Tesco's decision to take the rule-of-three a step further with another profits warning is no laughing matter or more satisfying/effective for loyal and battered shareholders," said Mike van Dulken, head of research at Accendo Markets.

"While new CEO Lewis and his team may be taking all the right steps to restore confidence in the UK's biggest grocer by market share after its accounting troubles of late and trying to keep the continually gaining cut-price competition at bay, the short-term impacts on profitability are being punished mercilessly with the shares trading -15% at 155p support levels dating back to 1999-2000 and 2003.

"Could this be where the real bargaining hunting begins, or is there too much risk still in the basket and a revisit of 150.00p on the cards," he said.