NEW YORK (TheStreet) -- Stocks rebounded sharply Tuesday after the long Labor Day weekend in the U.S.

The S&P 500 was up 1.5%, the Dow Jones Industrial Average added 1.6%, and the Nasdaq gained 1.8% in early trading.

General Electric (GE) - Get Report  maintained gains of 2% after the European Union approved its $17 billion acquisition of Alstom's power business. The approval will allow GE to go ahead with the its biggest ever deal.

In other deals news, Media General (MEG) surged nearly 10% after agreeing to acquire magazine publisher Meredith (MDP) - Get Report for $2.4 billion in a cash-and-stock deal. The combination will create the third-largest local TV station owner in the U.S.

Concordia Healthcare (CXRX) agreed to acquire niche pharmaceutical company Amdipharm Mercury from private-equity firm Cinven for $3.5 billion. The deal is expected to close in the fourth quarter.

Strategic Hotels (BEE) jumped nearly 4% after agreeing to be acquired by Blackstone Group (BX) - Get Report in a deal worth around $6 billion. Blackstone will pay $14.25 a share, a 13% premium on the intraday price in July when reports of a deal first broke.

China's Shanghai Composite closed 2.9% higher on hopes of further monetary stimulus after fresh trade data triggered more worries over the world's second-largest economy. China's exports fell in 5.5%, their second straight month of declines after a 8.3% decline in July. Imports fell 13.8%.

Separately, China's market regulators detailed plans to introduce a "circuit breaker" to rein in market volatility. Trading will be suspended if stocks swing more than 5% in any direction, while a 7% increase or decrease will close trading for the day.

U.S. markets have endured a wild ride over the past few weeks as investors fretted over the state of the global economy even as the U.S. economy continued to show signs of a robust rebound. Adding to the worry, a September rate hike from the Federal Reserve remained in play after a solid jobs report for August on Friday. The S&P 500 and Dow ended last week down 2.6%.

The Fed will meet on Sept. 16-17 to determine whether the U.S. economy is strong enough to withstand a move off of crises-level interest rates. 

Apple (AAPL) - Get Report shares jumped 2.8% ahead of its hardware event on Wednesday. The tech giant is expected to unveil the updated iPhone 6s and iPhone 6s Plus and a next-generation Apple TV line.

Bank of America (BAC) - Get Report is reportedly increasing efforts efforts to assure shareholders that CEO Brian Moynihan is suitable to also remain in his dual role as chairman. The bank has agreed to a Sept. 22 vote on the matter.

Chinese e-retailer JD.com (JD) - Get Report jumped more than 5% after announcing a share repurchase program of up to $1 billion over the next 24 months. Repurchases will be funded through the company's cash reserves.

Disney (DIS) - Get Report shares were on watch after the company expanded access to its on-demand entertainment to Amazon (AMZN) - Get Report and Microsoft (MSFT) - Get Report . The catalog is also available through Apple's iTunes and Google's (GOOGL) - Get Report Play.