(Close): US stock markets ended Tuesday mixed, as investors remain concerned about lower oil prices and political turmoil in Greece.
The Dow Jones dropped 51.28 points, or 0.29%, to 17,801.20 and the S&P 500 shed 0.49 points, or 0.02% to close at 2,059.82.
The Nasdaq index rose 25.77 points, or 0.54%, to finish at 4,766.57.
The day's biggest loser was Verizon, which saw its shares fall by 4% after a price war.
The firm is currently battling competitor AT&T to keep customers in the competitive mobile phone market.
Earlier, Greece brought forward the date of its next presidential election - a move which saw the country's main shares index slump by 10%. There was concern over whether the early election could jeopardise the country's bailout programme.
