One of Saturday's rockets exploded in a square inside the town, damaging a house. The other slammed into the outskirts of the town, causing no damage.
The armed wing of Hamas, the Izz al-Din al-Qassam Brigades, said it carried out the attack to avenge Israeli incursions in the West Bank and deadly air strikes on Friday that killed at least six of its fighters.
"We launched missiles at Sderot in retaliation for the Zionist aggressions against our nation, Israeli incursions into Tulkarim and other cities in the West Bank, and the latest Israeli missile attacks in Gaza and Salfit," it said.
Fighters fired 10 mortar rounds at Jewish settlements in Gaza overnight and three anti-tank rockets at Israeli military posts in the occupied territory, from which Israel is scheduled to withdraw next month.
The bombardments followed a series of Israeli air strikes on the occupied West Bank and Gaza Strip that killed at least six Hamas fighters on Friday.
The air raids were ordered after a Palestinian rocket attack on southern Israel killed a woman and was claimed by Hamas.
Also on Saturday, the Israeli army stopped Palestinians aged 16 to 35 from leaving the Gaza Strip, said Palestinian Interior Ministry spokesman Tawfek Abu Khousa.
Palestinian Prime Minister Ahmad Qureia held local and international media responsible for rising tensions.
The Palestinian Authority is not competing with any side, he said in a news conference on Saturday.
Prime Minister Ahmed Qureia
blames rising tension on the media
Qureia condemned the ongoing Israeli aggression in the Gaza Strip and some Palestinian cities.
These aggressions represent an Israeli attempt to escalate the situation and cause inter-Palestinian conflict, Qureia said.
Qureia has called on Palestinians to unite and support the PA.
Egypt will send senior security officials to the Gaza Strip on Sunday to try to restore calm, Egyptian officials said on Saturday.
Major-General Mustafa al-Behairy, deputy chief of the Egyptian intelligence will head the delegation.
The officials are expected to meet with leaders of Fatah and Hamas as well as Palestinian President Mahmoud Abbas, according to Egyptian officials, who spoke on condition of anonymity for fear of damaging the sensitive mediation effort.
Egypt has been a key mediator between Israel and the Palestinians and among the Palestinian factions.