The past weekend has been one of the most turbulent ever seen on Wall Street, in which some of the biggest names in the financial sector have been brought to their knees.

Lehman Brothers

The smallest of America's so-called bulge bracket banks said this morning that it had filed for Chapter 11 bankruptcy.

Rescue talks with rivals started on Friday and were overseen by the US Treasury. However, discussions failed after the authorities refused to give potential buyers billions of dollars in credit facilities to keep Lehman going until a deal was done.

Times Archive, 1929: Wall-Street panic

A Niagara of liquidation fell upon the American Stock Exchange today

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The US Treasury and Federal Reserve feared infuriating voters by rescuing another bank after pouring $29 billion (£16 billion) in federal funds into Bear Stearns in February, and backing Fannie Mae and Freddie Mac, the US mortgage debt giants, to the tune of $200 billion.

Barclays, the British bank, was a key player in the rescue talks but said today that it "did not proceed because it was not possible to conclude a transaction in the best interests of Barclays' shareholders".

Lehman said today that it would continue to try to sell its asset management businesses and would take action that should allow it to continue to manage its operations, including paying staff wages.

Merrill Lynch

Bank of America (BoA) and Merrill Lynch quietly agreed a deal in which Merrill will be bought by BoA for $50 billion in shares.

Merrill had been hard hit by the credit crunch, having written down more than $40 billion worth of assets over the past year. The deal will make BoA, one of America's bigget retail banks, a banking and investment management giant.

Merrill owns 45 per cent of BlackRock, the profitable asset manager worth more than $10 billion, which was apparently interested in buying Lehman Brother's fund management assets.

AIG

AIG, one of the world's biggest insurers, is looking for $40 billion in emergency funding. According to the New York Times, AIG has asked the Federal Reserve for a $40 billion short-term loan to fight off downgrades by credit rating agencies.

It is also reportedly hoping to raise up to $20 billion from investors that reportedly include the private equity firms Kohlberg Kravis Roberts, TPG and JC Flowers

The insurer has hired JPMorgan Chase to advise it on a refinancing package and will put out a trading statement today.

Banks' $70bn rescue fund

A group of banks, including BoA, JPMorgan Chase and Citigroup, are putting together a $70 billion fund to improve liquidity in the market.

Each of the participating companies will provide $7 billion to establish the fund and will be allowed to borrow up to a third of the total fund.

Other banks, such as Barclays, Credit Suisse, Deutsche Bank, Goldman Sachs, Morgan Stanley and UBS, will also take part and the fund could expand to allow other companies to join.

US Fed eases lending

The Federal Reserve said that it would make it easier for companies to access the central bank's cash by accepting a wider range of assets, including equities, as collateral for direct loans to investment banks.

The Fed, which is due to meet tomorrow to decide interest rates, also raised the size of the pool of available loans to $200 billion and suspended rules that prevent banks from using deposits to fund their investment banking businesses.

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