CAIRO, May 6 (Reuters) - Egypt's state-affiliated Al Qahera news TV on Monday quoted an unnamed "high-level" source as saying that Hamas's attack on Gaza's Kerem Shalom crossing had caused an impasse in ceasefire talks.

The Egyptian negotiators are intensifying talks to contain the current escalation between Israel and Hamas, the source said according to the channel. (Reporting by Jaidaa Taha; Editing by Nadine Awadalla)