The Sensex at the Bombay Stock Exchange tanked 268 points, or 1.6 percent, to slump below the 17,000-point level for the first time since March 5, at 16,869, in opening trade, this morning. Remaining weak, the Sensex stood 222 points, or 1.3 percent in the red, at 16,915, a short while ago. The domestic markets fell in line with the meltdown in the global markets, on concerns that Greece's debt crisis could spread to other countries. Other Asian markets in Hong Kong, Indonesia, Taiwan, and Singapore were down by between 0.5 percent and 3 percent, today. The US Dow Jones Industrial Average had plunged over 2 per cent, overnight.