London's FTSE 100 index stumbled to triple-digit losses by midday on Wednesday, as growing unrest in Egypt and political upheaval in Portugal unsettled investors already rattled by concerns over slowing growth in China and signs the US Federal Reserve may choose to temper stimulus.

The benchmark continued its recent retreat, shedding 105.5 points at 6,198.5. The FTSE 250 was also also firmly in negative territory, tumbling 127.5 points to 13,882.5.

One of the day's fallers was Domino's Pizza (DOM), which fell 48.5p or 7.25% to 620.5p on Germany-related disappointments.

In a trading update, the £1.1 billion cap pizza delivery company reported UK like-for-like sales growth of 6.1% for the second quarter to 30 June. This took first half like-for-like sales growth to 6.4% against some demanding prior year comparatives.

A slowdown in like-for-like sales in Germany in the second quarter, as well as a warning of wider-than-expected German losses due to underperforming corporate stores and higher training costs, caused investors to head for the exits.

One analyst to downgrade his numbers was Numis Securities' Douglas Jack, who cut his full-year profit before tax estimate by £2 million to £48.5 million on the news.

Shares in Cineworld (CINE) enjoyed a good session, surging almost 6% to 359.25p on a strong first-half pre close trading update. Over the 26 weeks ended 27 June, the group's total revenues rose 21.9% higher as its box office market share increased to 27.2%.

The £509 million cap also pleased punters with news of increasing admissions, higher average spend per person as well as higher year-on-year screen advertising revenues.

A bullish first half trading update from FTSE 100 oil explorer Tullow Oil (TLW) helped its shares to gush higher in a falling market, as we discuss in more detail here.

Telecoms equipment supplier Spirent (SPT) dealt the market another ugly profit warning as major buyers continue to resist investment. It means half-year revenues of around $93 million will be 22% down year-on-year despite encouraging longer-term orders building up.

Shares spelt out the troubles facing Spirent in April (here), and the market reacted by slashing 8% off the shares to 123.9p today.

Stadium Group (SDM:AIM) crashed over 23% to 32p after warning that profits would be 'significantly below market expectations.' The contract electronics manufacturing space is ugly and Stadium has been forced to delay closing its factory in Rugby, implying cost savings being moved to the right.

Hydrogen fuel stack developer ITM Power (ITM:AIM) has been forced to put its profits breakthrough on hold as hydrogen infrastructure technology investment stalls. That has hit hoped for revenues and sparked a 33.5% collapse in the shares to 32p today.

Regulated markets software microcap Ideagen (IDEA:AIM) has bolstered its NHS exposure by buying A&E monitoring specialist MSS in a deal worth up to £1.2 million.

The MSS Patient First suite could open the door to much bigger UK health service applications and the market likes the 60% recurring revenues from the acquired business. Shares in Ideagen nudged up 3.5% to 18.9p on the news.

Elsewhere, the market lapped up two announcements from AIM-quoted unconventional oil & gas play San Leon Energy (SLE:AIM) as it shares rose 25.5% to 6.3p. The group indicated it had successfully completed the hydraulic fracture of its Lewino-1G2 well in Poland's Baltic basin and also announced a farm-in deal on other Baltic basin assets with private firm Wisent Oil & Gas.

Shares in International Greetings (IGR:AIM) edged up 3.2% to 32.5p as the gift packaging and greetings cards maker unveiled double-digit growth in annual earnings per share. Click here to read our story.

Drug discovery and development company Summit (SUMM:AIM) improved 5.8% to 4.5p after announcing a placing to raise £4.5 million at 5p, a 17.6% premium to yesterday?s 4.25p closing price. The proceeds will enable Summit to continue its development programmes to treat muscle wasting condition Duchenne muscular dystrophy (DMD) and the Clostridium difficile (C.diff) bug.

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Issue Date: 03 Jul 2013