1.   Dozens of passengers in cars and on bicycles passing over the subway site were killed, including many schoolchildren.

2.   Perhaps the virtue of the New York subway site is that, at least for now, it seems to be mostly about the subway.

3.   Police said the leaking gas accumulated at the subway construction site until a spark ignited it.

4.   Police said the water main carried the leaking gas into the subway construction site, where it collected until ignited by a spark.

5.   The gas then built up at the subway construction site until a spark set it off, they said.

6.   The government also ordered checks nationwide at all gas works, and demanded safety checks be made at other subway construction sites.

7.   The gas then leaked into the water main and collected at a nearby subway construction site until a spark ignited it an hour later.

8.   The force of the blast flipped heavy metal sheets serving as a temporary road at a subway construction site at the intersection.

9.   The leaked gas collected at a subway construction site until a spark set it off.

10.   Five others remained unaccounted for following the urban gas main explosion that tore through the subway site which was under construction.