LONDON -- The FTSE 100 (INDEX: ^FTSE) remains cautious, up just 22 points to 5,735 points as the European Central Bank meets amid recent troubles in eurozone banking and finance. Interest rates have been held at 0.75%, but attention is now focused on the news conference expected later today, with many awaiting an announcement of measures to deal with Spain's high borrowing costs.

But whatever's happening at the ECB, some shares in the FTSE indexes were suffering all by themselves. Here are three of today's fallers.

Spirent (LSE: SPT.L)
Spirent Communications shares were crushed today, sliding 14% to 145 pence upon the release of interim results.

Although first-half adjusted operating profit rose 9% to $63 million (from $57.8 million in the first half of last year), we were warned that business is weak in Europe and the second half is likely to fall to "mid to low single digit" growth.

But there was still a nice 10% rise in the interim dividend to 1.39 cents per share.

Thomas Cook (LSE: TCG.L)
Thomas Cook shares fell 2.4% to 16.3 pence as the struggling travel agent reported a widening quarterly loss. For the three months to June 30, an operating loss of 26.5 million pounds was recorded, compared with a 20.1 million pound profit for the same quarter a year earlier. Revenue was down 6%, and net debt was up to 1.1 billion pounds from 900 million pounds 12 months earlier.

New chief executive Harriet Green said, "My initial focus is to review our businesses, quickly establish priorities and develop a clear plan to reinvigorate Thomas Cook, which I expect to be able to present to you next Spring." Now there's an idea -- but I'm not buying any shares.

Ophir (LSE: OPHR.L)
Ophir Energy shares slid 9% to 529.5 pence, despite the oil and gas producer's new gas discovery off the coast of Tanzania, taking it to six in a row for its offshore blocks one, three, and four.

But estimates of its productivity came in lower than previously expected, with a preliminary analysis suggesting there is between 0.5 trillion and 2 trillion cubic feet of gas there, whereas initial estimates had suggested around 3.1 tcf.

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